Hormones secreted by the PITUITARY GLAND including those from the anterior lobe (adenohypophysis), the posterior lobe (neurohypophysis), and the ill-defined intermediate lobe. Structurally, they include small peptides, proteins, and glycoproteins. They are under the regulation of neural signals (NEUROTRANSMITTERS) or neuroendocrine signals (HYPOTHALAMIC HORMONES) from the hypothalamus as well as feedback from their targets such as ADRENAL CORTEX HORMONES; ANDROGENS; ESTROGENS.
Hormones secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Structurally, they include polypeptide, protein, and glycoprotein molecules.
A small, unpaired gland situated in the SELLA TURCICA. It is connected to the HYPOTHALAMUS by a short stalk which is called the INFUNDIBULUM.
Neoplasms which arise from or metastasize to the PITUITARY GLAND. The majority of pituitary neoplasms are adenomas, which are divided into non-secreting and secreting forms. Hormone producing forms are further classified by the type of hormone they secrete. Pituitary adenomas may also be characterized by their staining properties (see ADENOMA, BASOPHIL; ADENOMA, ACIDOPHIL; and ADENOMA, CHROMOPHOBE). Pituitary tumors may compress adjacent structures, including the HYPOTHALAMUS, several CRANIAL NERVES, and the OPTIC CHIASM. Chiasmal compression may result in bitemporal HEMIANOPSIA.
Diminution or cessation of secretion of one or more hormones from the anterior pituitary gland (including LH; FOLLICLE STIMULATING HORMONE; SOMATOTROPIN; and CORTICOTROPIN). This may result from surgical or radiation ablation, non-secretory PITUITARY NEOPLASMS, metastatic tumors, infarction, PITUITARY APOPLEXY, infiltrative or granulomatous processes, and other conditions.
The anterior glandular lobe of the pituitary gland, also known as the adenohypophysis. It secretes the ADENOHYPOPHYSEAL HORMONES that regulate vital functions such as GROWTH; METABOLISM; and REPRODUCTION.
A lactogenic hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). It is a polypeptide of approximately 23 kD. Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation. Prolactin receptors are present in the mammary gland, hypothalamus, liver, ovary, testis, and prostate.
Disorders involving either the ADENOHYPOPHYSIS or the NEUROHYPOPHYSIS. These diseases usually manifest as hypersecretion or hyposecretion of PITUITARY HORMONES. Neoplastic pituitary masses can also cause compression of the OPTIC CHIASM and other adjacent structures.
Hormones released from the neurohypophysis (PITUITARY GLAND, POSTERIOR). They include a number of peptides which are formed in the NEURONS in the HYPOTHALAMUS, bound to NEUROPHYSINS, and stored in the nerve terminals in the posterior pituitary. Upon stimulation, these peptides are released into the hypophysial portal vessel blood.
A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.
A polypeptide that is secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Growth hormone, also known as somatotropin, stimulates mitosis, cell differentiation and cell growth. Species-specific growth hormones have been synthesized.
An anterior pituitary hormone that stimulates the ADRENAL CORTEX and its production of CORTICOSTEROIDS. ACTH is a 39-amino acid polypeptide of which the N-terminal 24-amino acid segment is identical in all species and contains the adrenocorticotrophic activity. Upon further tissue-specific processing, ACTH can yield ALPHA-MSH and corticotrophin-like intermediate lobe peptide (CLIP).
A 191-amino acid polypeptide hormone secreted by the human adenohypophysis (PITUITARY GLAND, ANTERIOR), also known as GH or somatotropin. Synthetic growth hormone, termed somatropin, has replaced the natural form in therapeutic usage such as treatment of dwarfism in children with growth hormone deficiency.
A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.
A glycoprotein hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Thyrotropin stimulates THYROID GLAND by increasing the iodide transport, synthesis and release of thyroid hormones (THYROXINE and TRIIODOTHYRONINE). Thyrotropin consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the pituitary glycoprotein hormones (TSH; LUTEINIZING HORMONE and FSH), but the beta subunit is unique and confers its biological specificity.
Chemical substances having a specific regulatory effect on the activity of a certain organ or organs. The term was originally applied to substances secreted by various ENDOCRINE GLANDS and transported in the bloodstream to the target organs. It is sometimes extended to include those substances that are not produced by the endocrine glands but that have similar effects.
Examinations that evaluate functions of the pituitary gland.
A form of dwarfism caused by complete or partial GROWTH HORMONE deficiency, resulting from either the lack of GROWTH HORMONE-RELEASING FACTOR from the HYPOTHALAMUS or from the mutations in the growth hormone gene (GH1) in the PITUITARY GLAND. It is also known as Type I pituitary dwarfism. Human hypophysial dwarf is caused by a deficiency of HUMAN GROWTH HORMONE during development.
Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)
Polypeptide hormones produced in the hypothalamus which inhibit the release of pituitary hormones. Used for PHRIH in general or for which there is no specific heading.
A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND.
Hormones secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR) that stimulate gonadal functions in both males and females. They include FOLLICLE STIMULATING HORMONE that stimulates germ cell maturation (OOGENESIS; SPERMATOGENESIS), and LUTEINIZING HORMONE that stimulates the production of sex steroids (ESTROGENS; PROGESTERONE; ANDROGENS).
A benign epithelial tumor with a glandular organization.
Neural tissue of the pituitary gland, also known as the neurohypophysis. It consists of the distal AXONS of neurons that produce VASOPRESSIN and OXYTOCIN in the SUPRAOPTIC NUCLEUS and the PARAVENTRICULAR NUCLEUS. These axons travel down through the MEDIAN EMINENCE, the hypothalamic infundibulum of the PITUITARY STALK, to the posterior lobe of the pituitary gland.
Natural hormones secreted by the THYROID GLAND, such as THYROXINE, and their synthetic analogs.
A tripeptide that stimulates the release of THYROTROPIN and PROLACTIN. It is synthesized by the neurons in the PARAVENTRICULAR NUCLEUS of the HYPOTHALAMUS. After being released into the pituitary portal circulation, TRH (was called TRF) stimulates the release of TSH and PRL from the ANTERIOR PITUITARY GLAND.
A pituitary adenoma which secretes PROLACTIN, leading to HYPERPROLACTINEMIA. Clinical manifestations include AMENORRHEA; GALACTORRHEA; IMPOTENCE; HEADACHE; visual disturbances; and CEREBROSPINAL FLUID RHINORRHEA.
The sudden loss of blood supply to the PITUITARY GLAND, leading to tissue NECROSIS and loss of function (PANHYPOPITUITARISM). The most common cause is hemorrhage or INFARCTION of a PITUITARY ADENOMA. It can also result from acute hemorrhage into SELLA TURCICA due to HEAD TRAUMA; INTRACRANIAL HYPERTENSION; or other acute effects of central nervous system hemorrhage. Clinical signs include severe HEADACHE; HYPOTENSION; bilateral visual disturbances; UNCONSCIOUSNESS; and COMA.
A peptide of 44 amino acids in most species that stimulates the release and synthesis of GROWTH HORMONE. GHRF (or GRF) is synthesized by neurons in the ARCUATE NUCLEUS of the HYPOTHALAMUS. After being released into the pituitary portal circulation, GHRF stimulates GH release by the SOMATOTROPHS in the PITUITARY GLAND.
A POU domain factor that regulates expression of GROWTH HORMONE; PROLACTIN; and THYROTROPIN-BETA in the ANTERIOR PITUITARY GLAND.
A 30-kDa protein synthesized primarily in the ANTERIOR PITUITARY GLAND and the HYPOTHALAMUS. It is also found in the skin and other peripheral tissues. Depending on species and tissues, POMC is cleaved by PROHORMONE CONVERTASES yielding various active peptides including ACTH; BETA-LIPOTROPIN; ENDORPHINS; MELANOCYTE-STIMULATING HORMONES; and others (GAMMA-LPH; CORTICOTROPIN-LIKE INTERMEDIATE LOBE PEPTIDE; N-terminal peptide of POMC or NPP).
A small tumor of the anterior lobe of the pituitary gland whose cells stain with basic dyes. It may give rise to excessive secretion of ACTH, resulting in CUSHING SYNDROME. (Dorland, 27th ed)
Peptides, natural or synthetic, that stimulate the release of PITUITARY HORMONES. They were first isolated from the extracts of the HYPOTHALAMUS; MEDIAN EMINENCE; PITUITARY STALK; and NEUROHYPOPHYSIS. In addition, some hypophysiotropic hormones control pituitary cell differentiation, cell proliferation, and hormone synthesis. Some can act on more than one pituitary hormone.
Steroid hormones produced by the GONADS. They stimulate reproductive organs, germ cell maturation, and the secondary sex characteristics in the males and the females. The major sex steroid hormones include ESTRADIOL; PROGESTERONE; and TESTOSTERONE.
The beta subunit of follicle stimulating hormone. It is a 15-kDa glycopolypeptide. Full biological activity of FSH requires the non-covalently bound heterodimers of an alpha and a beta subunit. Mutation of the FSHB gene causes delayed puberty, or infertility.
A condition resulting from congenital malformations involving the brain. The syndrome of septo-optic dysplasia combines hypoplasia or agenesis of the SEPTUM PELLUCIDUM and the OPTIC NERVE. The extent of the abnormalities can vary. Septo-optic dysplasia is often associated with abnormalities of the hypothalamic and other diencephalic structures, and HYPOPITUITARISM.
A multi-function neuropeptide that acts throughout the body by elevating intracellular cyclic AMP level via its interaction with PACAP RECEPTORS. Although first isolated from hypothalamic extracts and named for its action on the pituitary, it is widely distributed in the central and peripheral nervous systems. PACAP is important in the control of endocrine and homeostatic processes, such as secretion of pituitary and gut hormones and food intake.
The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (MONOIODOTYROSINE) and the coupling of iodotyrosines (DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism.
Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE.
Increased levels of PROLACTIN in the BLOOD, which may be associated with AMENORRHEA and GALACTORRHEA. Relatively common etiologies include PROLACTINOMA, medication effect, KIDNEY FAILURE, granulomatous diseases of the PITUITARY GLAND, and disorders which interfere with the hypothalamic inhibition of prolactin release. Ectopic (non-pituitary) production of prolactin may also occur. (From Joynt, Clinical Neurology, 1992, Ch36, pp77-8)
The main glucocorticoid secreted by the ADRENAL CORTEX. Its synthetic counterpart is used, either as an injection or topically, in the treatment of inflammation, allergy, collagen diseases, asthma, adrenocortical deficiency, shock, and some neoplastic conditions.
A peptide of about 41 amino acids that stimulates the release of ADRENOCORTICOTROPIC HORMONE. CRH is synthesized by neurons in the PARAVENTRICULAR NUCLEUS of the HYPOTHALAMUS. After being released into the pituitary portal circulation, CRH stimulates the release of ACTH from the PITUITARY GLAND. CRH can also be synthesized in other tissues, such as PLACENTA; ADRENAL MEDULLA; and TESTIS.
A subclass of LIM domain proteins that include an additional centrally-located homeodomain region that binds AT-rich sites on DNA. Many LIM-homeodomain proteins play a role as transcriptional regulators that direct cell fate.
The alpha chain of pituitary glycoprotein hormones (THYROTROPIN; FOLLICLE STIMULATING HORMONE; LUTEINIZING HORMONE) and the placental CHORIONIC GONADOTROPIN. Within a species, the alpha subunits of these four hormones are identical; the distinct functional characteristics of these glycoprotein hormones are determined by the unique beta subunits. Both subunits, the non-covalently bound heterodimers, are required for full biologic activity.
A collection of NEURONS, tracts of NERVE FIBERS, endocrine tissue, and blood vessels in the HYPOTHALAMUS and the PITUITARY GLAND. This hypothalamo-hypophyseal portal circulation provides the mechanism for hypothalamic neuroendocrine (HYPOTHALAMIC HORMONES) regulation of pituitary function and the release of various PITUITARY HORMONES into the systemic circulation to maintain HOMEOSTASIS.
A polypeptide hormone (84 amino acid residues) secreted by the PARATHYROID GLANDS which performs the essential role of maintaining intracellular CALCIUM levels in the body. Parathyroid hormone increases intracellular calcium by promoting the release of CALCIUM from BONE, increases the intestinal absorption of calcium, increases the renal tubular reabsorption of calcium, and increases the renal excretion of phosphates.
A benign pituitary-region neoplasm that originates from Rathke's pouch. The two major histologic and clinical subtypes are adamantinous (or classical) craniopharyngioma and papillary craniopharyngioma. The adamantinous form presents in children and adolescents as an expanding cystic lesion in the pituitary region. The cystic cavity is filled with a black viscous substance and histologically the tumor is composed of adamantinomatous epithelium and areas of calcification and necrosis. Papillary craniopharyngiomas occur in adults, and histologically feature a squamous epithelium with papillations. (From Joynt, Clinical Neurology, 1998, Ch14, p50)
A bony prominence situated on the upper surface of the body of the sphenoid bone. It houses the PITUITARY GLAND.
The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
A potent androgenic steroid and major product secreted by the LEYDIG CELLS of the TESTIS. Its production is stimulated by LUTEINIZING HORMONE from the PITUITARY GLAND. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to DIHYDROTESTOSTERONE or ESTRADIOL.
Conditions in which the production of adrenal CORTICOSTEROIDS falls below the requirement of the body. Adrenal insufficiency can be caused by defects in the ADRENAL GLANDS, the PITUITARY GLAND, or the HYPOTHALAMUS.
A benign tumor, usually found in the anterior lobe of the pituitary gland, whose cells stain with acid dyes. Such pituitary tumors may give rise to excessive secretion of growth hormone, resulting in gigantism or acromegaly. A specific type of acidophil adenoma may give rise to nonpuerperal galactorrhea. (Dorland, 27th ed)
Congenital or acquired cysts of the brain, spinal cord, or meninges which may remain stable in size or undergo progressive enlargement.
Condition resulting from deficient gonadal functions, such as GAMETOGENESIS and the production of GONADAL STEROID HORMONES. It is characterized by delay in GROWTH, germ cell maturation, and development of secondary sex characteristics. Hypogonadism can be due to a deficiency of GONADOTROPINS (hypogonadotropic hypogonadism) or due to primary gonadal failure (hypergonadotropic hypogonadism).
Therapeutic use of hormones to alleviate the effects of hormone deficiency.
A genetic or acquired polyuric disorder caused by a deficiency of VASOPRESSINS secreted by the NEUROHYPOPHYSIS. Clinical signs include the excretion of large volumes of dilute URINE; HYPERNATREMIA; THIRST; and polydipsia. Etiologies include HEAD TRAUMA; surgeries and diseases involving the HYPOTHALAMUS and the PITUITARY GLAND. This disorder may also be caused by mutations of genes such as ARVP encoding vasopressin and its corresponding neurophysin (NEUROPHYSINS).
Pathological processes of the ENDOCRINE GLANDS, and diseases resulting from abnormal level of available HORMONES.
A syndrome that results from abnormally low secretion of THYROID HORMONES from the THYROID GLAND, leading to a decrease in BASAL METABOLIC RATE. In its most severe form, there is accumulation of MUCOPOLYSACCHARIDES in the SKIN and EDEMA, known as MYXEDEMA.
Cell surface proteins that bind pituitary hormones with high affinity and trigger intracellular changes influencing the behavior of cells. Since many pituitary hormones are also released by neurons as neurotransmitters, these receptors are also found in the nervous system.
Neoplastic, inflammatory, infectious, and other diseases of the hypothalamus. Clinical manifestations include appetite disorders; AUTONOMIC NERVOUS SYSTEM DISEASES; SLEEP DISORDERS; behavioral symptoms related to dysfunction of the LIMBIC SYSTEM; and neuroendocrine disorders.
Specific high affinity binding proteins for THYROID HORMONES in target cells. They are usually found in the nucleus and regulate DNA transcription. These receptors are activated by hormones that leads to transcription, cell differentiation, and growth suppression. Thyroid hormone receptors are encoded by two genes (GENES, ERBA): erbA-alpha and erbA-beta for alpha and beta thyroid hormone receptors, respectively.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
A pituitary tumor that secretes GROWTH HORMONE. In humans, excess HUMAN GROWTH HORMONE leads to ACROMEGALY.
A mobile, very volatile, highly flammable liquid used as an inhalation anesthetic and as a solvent for waxes, fats, oils, perfumes, alkaloids, and gums. It is mildly irritating to skin and mucous membranes.
The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.
A disease of the PITUITARY GLAND characterized by the excess amount of ADRENOCORTICOTROPIC HORMONE secreted. This leads to hypersecretion of cortisol (HYDROCORTISONE) by the ADRENAL GLANDS resulting in CUSHING SYNDROME.
Labile proteins on or in prolactin-sensitive cells that bind prolactin initiating the cells' physiological response to that hormone. Mammary casein synthesis is one of the responses. The receptors are also found in placenta, liver, testes, kidneys, ovaries, and other organs and bind and respond to certain other hormones and their analogs and antagonists. This receptor is related to the growth hormone receptor.
A pituitary adenoma which secretes ADRENOCORTICOTROPIN, leading to CUSHING DISEASE.
Methods and procedures for the diagnosis of diseases or dysfunction of the endocrine glands or demonstration of their physiological processes.
A genetic or pathological condition that is characterized by short stature and undersize. Abnormal skeletal growth usually results in an adult who is significantly below the average height.
A 14-amino acid peptide named for its ability to inhibit pituitary GROWTH HORMONE release, also called somatotropin release-inhibiting factor. It is expressed in the central and peripheral nervous systems, the gut, and other organs. SRIF can also inhibit the release of THYROID-STIMULATING HORMONE; PROLACTIN; INSULIN; and GLUCAGON besides acting as a neurotransmitter and neuromodulator. In a number of species including humans, there is an additional form of somatostatin, SRIF-28 with a 14-amino acid extension at the N-terminal.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.
A T3 thyroid hormone normally synthesized and secreted by the thyroid gland in much smaller quantities than thyroxine (T4). Most T3 is derived from peripheral monodeiodination of T4 at the 5' position of the outer ring of the iodothyronine nucleus. The hormone finally delivered and used by the tissues is mainly T3.
The surgical removal of one or both ovaries.
A group of acidic proteins that are major components of SECRETORY GRANULES in the endocrine and neuroendocrine cells. They play important roles in the aggregation, packaging, sorting, and processing of secretory protein prior to secretion. They are cleaved to release biologically active peptides. There are various types of granins, usually classified by their sources.
Achievement of full sexual capacity in animals and in humans.
Receptors with a 6-kDa protein on the surfaces of cells that secrete LUTEINIZING HORMONE or FOLLICLE STIMULATING HORMONE, usually in the adenohypophysis. LUTEINIZING HORMONE-RELEASING HORMONE binds to these receptors, is endocytosed with the receptor and, in the cell, triggers the release of LUTEINIZING HORMONE or FOLLICLE STIMULATING HORMONE by the cell. These receptors are also found in rat gonads. INHIBINS prevent the binding of GnRH to its receptors.
A well-characterized basic peptide believed to be secreted by the liver and to circulate in the blood. It has growth-regulating, insulin-like, and mitogenic activities. This growth factor has a major, but not absolute, dependence on GROWTH HORMONE. It is believed to be mainly active in adults in contrast to INSULIN-LIKE GROWTH FACTOR II, which is a major fetal growth factor.
Peptides released by NEURONS as intercellular messengers. Many neuropeptides are also hormones released by non-neuronal cells.
Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.
A system of NEURONS that has the specialized function to produce and secrete HORMONES, and that constitutes, in whole or in part, an ENDOCRINE SYSTEM or organ.
Compounds that interact with ESTROGEN RECEPTORS in target tissues to bring about the effects similar to those of ESTRADIOL. Estrogens stimulate the female reproductive organs, and the development of secondary female SEX CHARACTERISTICS. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds.
Proteins encoded by homeobox genes (GENES, HOMEOBOX) that exhibit structural similarity to certain prokaryotic and eukaryotic DNA-binding proteins. Homeodomain proteins are involved in the control of gene expression during morphogenesis and development (GENE EXPRESSION REGULATION, DEVELOPMENTAL).
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
A highly vascularized endocrine gland consisting of two lobes joined by a thin band of tissue with one lobe on each side of the TRACHEA. It secretes THYROID HORMONES from the follicular cells and CALCITONIN from the parafollicular cells thereby regulating METABOLISM and CALCIUM level in blood, respectively.
Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.
Deviations from the average values for a specific age and sex in any or all of the following: height, weight, skeletal proportions, osseous development, or maturation of features. Included here are both acceleration and retardation of growth.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
An adrenocortical steroid that has modest but significant activities as a mineralocorticoid and a glucocorticoid. (From Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1437)
Cell surface receptors that bind the hypothalamic hormones regulating pituitary cell differentiation, proliferation, and hormone synthesis and release, including the pituitary-releasing and release-inhibiting hormones. The pituitary hormone-regulating hormones are also released by cells other than hypothalamic neurons, and their receptors also occur on non-pituitary cells, especially brain neurons, where their role is less well understood. Receptors for dopamine, which is a prolactin release-inhibiting hormone as well as a common neurotransmitter, are not included here.
Anterior pituitary cells that can produce both FOLLICLE STIMULATING HORMONE and LUTEINIZING HORMONE.
A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).
The beta subunit of luteinizing hormone. It is a 15-kDa glycopolypeptide with structure similar to the beta subunit of the placental chorionic gonadatropin (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN) except for the additional 31 amino acids at the C-terminal of CG-beta. Full biological activity of LH requires the non-covalently bound heterodimers of an alpha and a beta subunit. Mutation of the LHB gene causes HYPOGONADISM and infertility.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
A condition caused by prolonged exposure to excessive HUMAN GROWTH HORMONE in adults. It is characterized by bony enlargement of the FACE; lower jaw (PROGNATHISM); hands; FEET; HEAD; and THORAX. The most common etiology is a GROWTH HORMONE-SECRETING PITUITARY ADENOMA. (From Joynt, Clinical Neurology, 1992, Ch36, pp79-80)
A benign tumor of the anterior pituitary in which the cells do not stain with acidic or basic dyes.
Anterior pituitary cells which produce GROWTH HORMONE.
Proteins obtained from species of fish (FISHES).
A family of G-protein-coupled receptors that share significant homology with GLUCAGON RECEPTORS. They bind PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE with high affinity and trigger intracellular changes that influence the behavior of CELLS.
Peptide hormones produced by NEURONS of various regions in the HYPOTHALAMUS. They are released into the pituitary portal circulation to stimulate or inhibit PITUITARY GLAND functions. VASOPRESSIN and OXYTOCIN, though produced in the hypothalamus, are not included here for they are transported down the AXONS to the POSTERIOR LOBE OF PITUITARY before being released into the portal circulation.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Peptides with the ability to stimulate pigmented cells MELANOCYTES in mammals and MELANOPHORES in lower vertebrates. By stimulating the synthesis and distribution of MELANIN in these pigmented cells, they increase coloration of skin and other tissue. MSHs, derived from pro-opiomelanocortin (POMC), are produced by MELANOTROPHS in the INTERMEDIATE LOBE OF PITUITARY; CORTICOTROPHS in the ANTERIOR LOBE OF PITUITARY, and the hypothalamic neurons in the ARCUATE NUCLEUS OF HYPOTHALAMUS.
Compounds, either natural or synthetic, which block development of the growing insect.
A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.
Radiation therapy used to treat the PITUITARY GLAND.
The discharge of an OVUM from a rupturing follicle in the OVARY.
Hormones synthesized from amino acids. They are distinguished from INTERCELLULAR SIGNALING PEPTIDES AND PROTEINS in that their actions are systemic.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Elements of limited time intervals, contributing to particular results or situations.
The intermediate lobe of the pituitary gland. It shows considerable size variation among the species, small in humans, and large in amphibians and lower vertebrates. This lobe produces mainly MELANOCYTE-STIMULATING HORMONES and other peptides from post-translational processing of pro-opiomelanocortin (POMC).
Hormones produced by the GONADS, including both steroid and peptide hormones. The major steroid hormones include ESTRADIOL and PROGESTERONE from the OVARY, and TESTOSTERONE from the TESTIS. The major peptide hormones include ACTIVINS and INHIBINS.
Type I Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) Receptor is a G protein-coupled receptor that binds PACAP and vasoactive intestinal polypeptide, activating adenylate cyclase and increasing intracellular cAMP levels upon activation.
Chemical substances which inhibit the function of the endocrine glands, the biosynthesis of their secreted hormones, or the action of hormones upon their specific sites.
An anti-inflammatory 9-fluoro-glucocorticoid.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
High affinity receptors for THYROID HORMONES, especially TRIIODOTHYRONINE. These receptors are usually found in the nucleus where they regulate DNA transcription. They are encoded by the THRB gene (also known as NR1A2, THRB1, or ERBA2 gene) as several isoforms produced by alternative splicing. Mutations in the THRB gene cause THYROID HORMONE RESISTANCE SYNDROME.
Cell surface receptors that bind thyrotropin releasing hormone (TRH) with high affinity and trigger intracellular changes which influence the behavior of cells. Activated TRH receptors in the anterior pituitary stimulate the release of thyrotropin (thyroid stimulating hormone, TSH); TRH receptors on neurons mediate neurotransmission by TRH.
A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Established cell cultures that have the potential to propagate indefinitely.
A glycoprotein that causes regression of MULLERIAN DUCTS. It is produced by SERTOLI CELLS of the TESTES. In the absence of this hormone, the Mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent Mullerian duct, a form of MALE PSEUDOHERMAPHRODITISM.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
The distance from the sole to the crown of the head with body standing on a flat surface and fully extended.
Surgical removal or artificial destruction of gonads.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Anterior pituitary cells that produce ADRENOCORTICOTROPHIC HORMONE.
HORMONES secreted by the gastrointestinal mucosa that affect the timing or the quality of secretion of digestive enzymes, and regulate the motor activity of the digestive system organs.
Anterior pituitary cells that produce PROLACTIN.
A semisynthetic ergotamine alkaloid that is a dopamine D2 agonist. It suppresses prolactin secretion.
Cell surface proteins that bind GROWTH HORMONE with high affinity and trigger intracellular changes influencing the behavior of cells. Activation of growth hormone receptors regulates amino acid transport through cell membranes, RNA translation to protein, DNA transcription, and protein and amino acid catabolism in many cell types. Many of these effects are mediated indirectly through stimulation of the release of somatomedins.
Proteins released by sensitized LYMPHOCYTES and possibly other cells that inhibit the migration of MACROPHAGES away from the release site. The structure and chemical properties may vary with the species and type of releasing cell.
Glycoproteins that inhibit pituitary FOLLICLE STIMULATING HORMONE secretion. Inhibins are secreted by the Sertoli cells of the testes, the granulosa cells of the ovarian follicles, the placenta, and other tissues. Inhibins and ACTIVINS are modulators of FOLLICLE STIMULATING HORMONE secretions; both groups belong to the TGF-beta superfamily, as the TRANSFORMING GROWTH FACTOR BETA. Inhibins consist of a disulfide-linked heterodimer with a unique alpha linked to either a beta A or a beta B subunit to form inhibin A or inhibin B, respectively
A condition caused by prolonged exposure to excess levels of cortisol (HYDROCORTISONE) or other GLUCOCORTICOIDS from endogenous or exogenous sources. It is characterized by upper body OBESITY; OSTEOPOROSIS; HYPERTENSION; DIABETES MELLITUS; HIRSUTISM; AMENORRHEA; and excess body fluid. Endogenous Cushing syndrome or spontaneous hypercortisolism is divided into two groups, those due to an excess of ADRENOCORTICOTROPIN and those that are ACTH-independent.
Securin is involved in the control of the metaphase-anaphase transition during MITOSIS. It promotes the onset of anaphase by blocking SEPARASE function and preventing proteolysis of cohesin and separation of sister CHROMATIDS. Overexpression of securin is associated with NEOPLASTIC CELL TRANSFORMATION and tumor formation.
Anterior pituitary cells that produce THYROID-STIMULATING HORMONE.
An irregular unpaired bone situated at the SKULL BASE and wedged between the frontal, temporal, and occipital bones (FRONTAL BONE; TEMPORAL BONE; OCCIPITAL BONE). Sphenoid bone consists of a median body and three pairs of processes resembling a bat with spread wings. The body is hollowed out in its inferior to form two large cavities (SPHENOID SINUS).
Hormones produced by the placenta include CHORIONIC GONADOTROPIN, and PLACENTAL LACTOGEN as well as steroids (ESTROGENS; PROGESTERONE), and neuropeptide hormones similar to those found in the hypothalamus (HYPOTHALAMIC HORMONES).
The interactions between the anterior pituitary and adrenal glands, in which corticotropin (ACTH) stimulates the adrenal cortex and adrenal cortical hormones suppress the production of corticotropin by the anterior pituitary.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
The beta subunit of thyroid stimulating hormone, thyrotropin. It is a 112-amino acid glycopolypeptide of about 16 kD. Full biological activity of TSH requires the non-covalently bound heterodimers of an alpha and a beta subunit.
High affinity receptors for THYROID HORMONES, especially TRIIODOTHYRONINE. These receptors are usually found in the nucleus where they regulate DNA transcription. They are encoded by the THRA gene (also known as NR1A1, THRA1, ERBA or ERBA1 gene) as several isoforms produced by alternative splicing.
Peptide hormones secreted into the blood by cells in the ISLETS OF LANGERHANS of the pancreas. The alpha cells secrete glucagon; the beta cells secrete insulin; the delta cells secrete somatostatin; and the PP cells secrete pancreatic polypeptide.
One of the three major groups of endogenous opioid peptides. They are large peptides derived from the PRO-OPIOMELANOCORTIN precursor. The known members of this group are alpha-, beta-, and gamma-endorphin. The term endorphin is also sometimes used to refer to all opioid peptides, but the narrower sense is used here; OPIOID PEPTIDES is used for the broader group.
Hormones secreted by insects. They influence their growth and development. Also synthetic substances that act like insect hormones.
Hormones produced in the testis.
One of the paired air spaces located in the body of the SPHENOID BONE behind the ETHMOID BONE in the middle of the skull. Sphenoid sinus communicates with the posterosuperior part of NASAL CAVITY on the same side.
The surgical removal of one or both testicles.
A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)
The period in the ESTROUS CYCLE associated with maximum sexual receptivity and fertility in non-primate female mammals.
Hormones produced by invertebrates, usually insects, mollusks, annelids, and helminths.
A 31-amino acid peptide that is the C-terminal fragment of BETA-LIPOTROPIN. It acts on OPIOID RECEPTORS and is an analgesic. Its first four amino acids at the N-terminal are identical to the tetrapeptide sequence of METHIONINE ENKEPHALIN and LEUCINE ENKEPHALIN.
The measurement of an organ in volume, mass, or heaviness.
The relationship between the dose of an administered drug and the response of the organism to the drug.
A disease that is characterized by frequent urination, excretion of large amounts of dilute URINE, and excessive THIRST. Etiologies of diabetes insipidus include deficiency of antidiuretic hormone (also known as ADH or VASOPRESSIN) secreted by the NEUROHYPOPHYSIS, impaired KIDNEY response to ADH, and impaired hypothalamic regulation of thirst.
A highly basic, 28 amino acid neuropeptide released from intestinal mucosa. It has a wide range of biological actions affecting the cardiovascular, gastrointestinal, and respiratory systems and is neuroprotective. It binds special receptors (RECEPTORS, VASOACTIVE INTESTINAL PEPTIDE).
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
A 90-amino acid peptide derived from post-translational processing of pro-opiomelanocortin (POMC) in the PITUITARY GLAND and the HYPOTHALAMUS. It is the C-terminal fragment of POMC with lipid-mobilizing activities, such as LIPOLYSIS and steroidogenesis. Depending on the species and the tissue sites, beta-LPH may be further processed to yield active peptides including GAMMA-LIPOTROPIN; BETA-MSH; and ENDORPHINS.
An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.
A hemeprotein that catalyzes the oxidation of the iodide radical to iodine with the subsequent iodination of many organic compounds, particularly proteins. EC 1.11.1.8.

Long term orexigenic effect of a novel melanocortin 4 receptor selective antagonist. (1/206)

1. We designed and synthesized several novel cyclic MSH analogues and tested their affinities for cells expressing the MC1, MC3, MC4 and MC5 receptors. 2. One of the substances HS028 (cyclic [AcCys11, dichloro-D-phenylalanine14, Cys18, Asp-NH2(22)]-beta-MSH11-22) showed high affinity (Ki of 0.95nM) and high (80 fold) MC4 receptor selectivity over the MC3 receptor. HS028 thus shows both higher affinity and higher selectivity for the MC4 receptor compared to the earlier first described MC4 receptor selective substance HS014. 3. HS028 antagonised a alpha-MSH induced increase in cyclic AMP production in transfected cells expressing the MC3 and MC4 receptors, whereas it seemed to be a partial agonist for the MC1 and MC5 receptors. 4. Chronic intracerebroventricularly (i.c.v.) administration of HS028 by osmotic minipumps significantly increased both food intake and body weight in a dose dependent manner without tachyphylaxis for a period of 7 days. 5. This is the first report demonstrating that an MC4 receptor antagonist can increase food intake and body weight during chronic administration providing further evidence that the MC4 receptor is an important mediator of long term weight homeostasis.  (+info)

alpha-MSH and its receptors in regulation of tumor necrosis factor-alpha production by human monocyte/macrophages. (2/206)

The hypothesis that macrophages contain an autocrine circuit based on melanocortin [ACTH and alpha-melanocyte-stimulating hormone (alpha-MSH)] peptides has major implications for neuroimmunomodulation research and inflammation therapy. To test this hypothesis, cells of the THP-1 human monocyte/macrophage line were stimulated with lipopolysaccharide (LPS) in the presence and absence of alpha-MSH. The inflammatory cytokine tumor necrosis factor (TNF)-alpha was inhibited in relation to alpha-MSH concentration. Similar inhibitory effects on TNF-alpha were observed with ACTH peptides that contain the alpha-MSH amino acid sequence and act on melanocortin receptors. Nuclease protection assays indicated that expression of the human melanocortin-1 receptor subtype (hMC-1R) occurs in THP-1 cells; Southern blots of RT-PCR product revealed that additional subtypes, hMC-3R and hMC-5R, also occur. Incubation of resting macrophages with antibody to hMC-1R increased TNF-alpha concentration; the antibody also markedly reduced the inhibitory influence of alpha-MSH on TNF-alpha in macrophages treated with LPS. These results in cells known to produce alpha-MSH at rest and to increase secretion of the peptide when challenged are consistent with an endogenous regulatory circuit based on melanocortin peptides and their receptors. Targeting of this neuroimmunomodulatory circuit in inflammatory diseases in which myelomonocytic cells are prominent should be beneficial.  (+info)

Regulation of basal expression of catecholamine-synthesizing enzyme genes by PACAP. (3/206)

We have previously reported that the cAMP/protein kinase A (PKA) pathway is important in the gene regulation of both induction and basal expressions of the catecholamine synthesizing enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). The neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) has been shown to activate the intracellular cAMP/PKA pathway. In the present study, using primary cultured bovine adrenal medullary cells, we determined whether the basal activity of the PACAP receptor might play a role in the maintenance of the basal expression of these enzyme genes via the cAMP/PKA pathway. The potent PACAP receptor antagonist PACAP (6-38) caused a reduction of TH and DBH mRNA levels in a dose dependent manner as well as their enzyme activities and TH protein level. The effects of PACAP (6-38) and the PKA inhibitor H-89 exhibited generally similar trends, and were not additive in the reduction of TH and DBH gene expression and activities, suggesting that they take a common intracellular signaling pathway. The antagonist also caused decreases in the intracellular norepinephrine and epinephrine levels similar to the effect of H-89. Taken together, the data suggests that PACAP is involved in the regulation of maintenance of the catecholamine synthesizing enzymes TH and DBH by utilizing the cAMP/PKA pathway.  (+info)

Enhanced expression of melanocortin-1 receptor (MC1-R) in normal human keratinocytes during differentiation: evidence for increased expression of POMC peptides near suprabasal layer of epidermis. (4/206)

Immunohistochemical staining of human skin specimen showed the stronger localization of proopiomelanocortin peptides near the suprabasal layer of the epidermis, where keratinocytes are mostly differentiated. To test the possibilities of whether the production of proopiomelanocortin peptides or their receptor-binding activity or both is increased during differentiation of keratinocytes, we treated the cells in culture with Ca2+ to induce their differentiation. The production of proopiomelanocortin peptides and its gene expression were not induced significantly, but the binding ability of melanocortin receptor, as well as its gene expression were stimulated by Ca2+. Ultraviolet B irradiation, an inducer of differentiation, stimulated both proopiomelanocortin production and melanocortin receptor expression. These data show that normal human keratinocytes express melanocortin receptor similar to melanocytes, and that it is induced during differentiation.  (+info)

Expression, pharmacological, and functional evidence for PACAP/VIP receptors in human lung. (5/206)

Pituitary adenylate cyclase-activating peptide (PACAP) type 1 (PAC(1)) and common PACAP/vasoactive intestinal peptide (VIP) type 1 and 2 (VPAC(1) and VPAC(2), respectively) receptors were detected in the human lung by RT-PCR. The proteins were identified by immunoblotting at 72, 67, and 68 kDa, respectively. One class of PACAP receptors was defined from (125)I-labeled PACAP-27 binding experiments (dissociation constant = 5.2 nM; maximum binding capacity = 5.2 pmol/mg protein) with a specificity: PACAP-27 approximately VIP > helodermin approximately peptide histidine-methionine (PHM) >> secretin. Two classes of VIP receptors were established with (125)I-VIP (dissociation constants of 5.4 and 197 nM) with a specificity: VIP approximately helodermin approximately PACAP-27 >> PHM >> secretin. PACAP-27 and VIP were equipotent on adenylyl cyclase stimulation (EC(50) = 1.6 nM), whereas other peptides showed lower potency (helodermin > PHM >> secretin). PACAP/VIP antagonists supported that PACAP-27 acts in the human lung through either specific receptors or common PACAP/VIP receptors. The present results are the first demonstration of the presence of PAC(1) receptors and extend our knowledge of common PACAP/VIP receptors in the human lung.  (+info)

High-voltage-activated calcium current and its modulation by dopamine D4 and pituitary adenylate cyclase activating polypeptide receptors in cerebellar granule cells. (6/206)

Cerebellar granule cells were a good mold for electrophysiologic studies at the single neuron level. Two distinct types of high-voltage-activated Ca2+ channels were present in cerebellar granule cells. These calcium channels change their expression, gating, and pharmacological properties during development, suggesting that calcium channel must be related to the processes of granule cell maturation and excitability. Dopamine inhibited L-type calcium current by activating D4 receptor, and this effect might involve another signaling system with the exception of cAMP system. The functional D4 receptor discovered in cerebellum not only gave a possibility to find other antipsychotics, but also supported the existence of a dopaminergic system in the granule cell involving the D4 receptor. Pituitary adenylate cyclase activating polypeptide (PACAP) could increase intracellular Ca2+ content by activation of Ca2+ channel and mobilization of intracellular Ca2+ stores. The effects were also cAMP-independent. Activating Ca2+ currents might be an important and necessary role of PACAP as a neurotropic factor involved in the control of multiplication, differentiation, and migration of granule cells.  (+info)

Functional characterization of structural alterations in the sequence of the vasodilatory peptide maxadilan yields a pituitary adenylate cyclase-activating peptide type 1 receptor-specific antagonist. (7/206)

Maxadilan is a vasodilatory peptide derived from sand flies that is an agonist at the pituitary adenylate cyclase-activating peptide (PACAP) type 1 receptor. Surprisingly, maxadilan does not share significant sequence homology with PACAP. To examine the relationship between structure and activity of maxadilan, several amino acid substitutions and deletions were made in the peptide. These peptides were examined in vitro for binding to crude membranes derived from rabbit brain, a tissue that expresses PACAP type 1 receptors; and induction of cAMP was determined in PC12 cells, a line that expresses these receptors. The peptides were examined in vivo for their ability to induce erythema in rabbit skin. Substitution of the individual cysteines at positions 1 and 5 or deletion of this ring structure had little effect on activity. Substitution of either cysteine at position 14 or 51 eliminated activity. Deletion of the 19 amino acids between positions 24 and 42 resulted in a peptide with binding, but no functional activity. The capacity of this deletion mutant to interact with COS cells transfected with the PACAP type 1 receptor revealed that this peptide was a specific antagonist to the PACAP type 1 receptor.  (+info)

Pituitary adenylate cyclase-activating polypeptides directly stimulate sympathetic neuron neuropeptide Y release through PAC(1) receptor isoform activation of specific intracellular signaling pathways. (8/206)

Pituitary adenylate cyclase-activating polypeptides (PACAP) have potent regulatory and neurotrophic activities on superior cervical ganglion (SCG) sympathetic neurons with pharmacological profiles consistent for the PACAP-selective PAC(1) receptor. Multiple PAC(1) receptor isoforms are suggested to determine differential peptide potency and receptor coupling to multiple intracellular signaling pathways. The current studies examined rat SCG PAC(1) receptor splice variant expression and coupling to intracellular signaling pathways mediating PACAP-stimulated peptide release. PAC(1) receptor mRNA was localized in over 90% of SCG neurons, which correlated with the cells expressing receptor protein. The neurons expressed the PAC(1)(short)HOP1 receptor but not VIP/PACAP-nonselective VPAC(1) receptors; low VPAC(2) receptor mRNA levels were restricted to ganglionic nonneuronal cells. PACAP27 and PACAP38 potently and efficaciously stimulated both cAMP and inositol phosphate production; inhibition of phospholipase C augmented PACAP-stimulated cAMP production, but inhibition of adenylyl cyclase did not alter stimulated inositol phosphate production. Phospholipase C inhibition blunted neuron peptide release, suggesting that the phosphatidylinositol pathway was a prominent component of the secretory response. These studies demonstrate preferential sympathetic neuron expression of PACAP-selective receptor variants contributing to regulation of autonomic function.  (+info)

Pituitary hormones are chemical messengers produced and released by the pituitary gland, a small endocrine gland located at the base of the brain. The pituitary gland is often referred to as the "master gland" because it controls several other endocrine glands and regulates various bodily functions.

There are two main types of pituitary hormones: anterior pituitary hormones and posterior pituitary hormones, which are produced in different parts of the pituitary gland and have distinct functions.

Anterior pituitary hormones include:

1. Growth hormone (GH): regulates growth and metabolism.
2. Thyroid-stimulating hormone (TSH): stimulates the thyroid gland to produce thyroid hormones.
3. Adrenocorticotropic hormone (ACTH): stimulates the adrenal glands to produce cortisol and other steroid hormones.
4. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH): regulate reproductive function in both males and females.
5. Prolactin: stimulates milk production in lactating women.
6. Melanocyte-stimulating hormone (MSH): regulates skin pigmentation and appetite.

Posterior pituitary hormones include:

1. Oxytocin: stimulates uterine contractions during childbirth and milk ejection during lactation.
2. Vasopressin (antidiuretic hormone, ADH): regulates water balance in the body by controlling urine production in the kidneys.

Overall, pituitary hormones play crucial roles in regulating growth, development, metabolism, reproductive function, and various other bodily functions. Abnormalities in pituitary hormone levels can lead to a range of medical conditions, such as dwarfism, acromegaly, Cushing's disease, infertility, and diabetes insipidus.

Anterior pituitary hormones are a group of six major hormones that are produced and released by the anterior portion (lobe) of the pituitary gland, a small endocrine gland located at the base of the brain. These hormones play crucial roles in regulating various bodily functions and activities. The six main anterior pituitary hormones are:

1. Growth Hormone (GH): Also known as somatotropin, GH is essential for normal growth and development in children and adolescents. It helps regulate body composition, metabolism, and bone density in adults.
2. Prolactin (PRL): A hormone that stimulates milk production in females after childbirth and is also involved in various reproductive and immune functions in both sexes.
3. Follicle-Stimulating Hormone (FSH): FSH regulates the development, growth, and maturation of follicles in the ovaries (in females) and sperm production in the testes (in males).
4. Luteinizing Hormone (LH): LH plays a key role in triggering ovulation in females and stimulating testosterone production in males.
5. Thyroid-Stimulating Hormone (TSH): TSH regulates the function of the thyroid gland, which is responsible for producing and releasing thyroid hormones that control metabolism and growth.
6. Adrenocorticotropic Hormone (ACTH): ACTH stimulates the adrenal glands to produce cortisol, a steroid hormone involved in stress response, metabolism, and immune function.

These anterior pituitary hormones are regulated by the hypothalamus, which is located above the pituitary gland. The hypothalamus releases releasing and inhibiting factors that control the synthesis and secretion of anterior pituitary hormones, creating a complex feedback system to maintain homeostasis in the body.

The pituitary gland is a small, endocrine gland located at the base of the brain, in the sella turcica of the sphenoid bone. It is often called the "master gland" because it controls other glands and makes the hormones that trigger many body functions. The pituitary gland measures about 0.5 cm in height and 1 cm in width, and it weighs approximately 0.5 grams.

The pituitary gland is divided into two main parts: the anterior lobe (adenohypophysis) and the posterior lobe (neurohypophysis). The anterior lobe is further divided into three zones: the pars distalis, pars intermedia, and pars tuberalis. Each part of the pituitary gland has distinct functions and produces different hormones.

The anterior pituitary gland produces and releases several important hormones, including:

* Growth hormone (GH), which regulates growth and development in children and helps maintain muscle mass and bone strength in adults.
* Thyroid-stimulating hormone (TSH), which controls the production of thyroid hormones by the thyroid gland.
* Adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to produce cortisol and other steroid hormones.
* Follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which regulate reproductive function in both males and females.
* Prolactin, which stimulates milk production in pregnant and lactating women.

The posterior pituitary gland stores and releases two hormones that are produced by the hypothalamus:

* Antidiuretic hormone (ADH), which helps regulate water balance in the body by controlling urine production.
* Oxytocin, which stimulates uterine contractions during childbirth and milk release during breastfeeding.

Overall, the pituitary gland plays a critical role in maintaining homeostasis and regulating various bodily functions, including growth, development, metabolism, and reproductive function.

Pituitary neoplasms refer to abnormal growths or tumors in the pituitary gland, a small endocrine gland located at the base of the brain. These neoplasms can be benign (non-cancerous) or malignant (cancerous), with most being benign. They can vary in size and may cause various symptoms depending on their location, size, and hormonal activity.

Pituitary neoplasms can produce and secrete excess hormones, leading to a variety of endocrine disorders such as Cushing's disease (caused by excessive ACTH production), acromegaly (caused by excessive GH production), or prolactinoma (caused by excessive PRL production). They can also cause local compression symptoms due to their size, leading to headaches, vision problems, and cranial nerve palsies.

The exact causes of pituitary neoplasms are not fully understood, but genetic factors, radiation exposure, and certain inherited conditions may increase the risk of developing these tumors. Treatment options for pituitary neoplasms include surgical removal, radiation therapy, and medical management with drugs that can help control hormonal imbalances.

Hypopituitarism is a medical condition characterized by deficient secretion of one or more hormones produced by the pituitary gland, a small endocrine gland located at the base of the brain. The pituitary gland controls several other endocrine glands in the body, including the thyroid, adrenals, and sex glands (ovaries and testes).

Hypopituitarism can result from damage to the pituitary gland due to various causes such as tumors, surgery, radiation therapy, trauma, or inflammation. In some cases, hypopituitarism may also be caused by a dysfunction of the hypothalamus, a region in the brain that regulates the pituitary gland's function.

The symptoms and signs of hypopituitarism depend on which hormones are deficient and can include fatigue, weakness, decreased appetite, weight loss, low blood pressure, decreased sex drive, infertility, irregular menstrual periods, intolerance to cold, constipation, thinning hair, dry skin, and depression.

Treatment of hypopituitarism typically involves hormone replacement therapy to restore the deficient hormones' normal levels. The type and dosage of hormones used will depend on which hormones are deficient and may require regular monitoring and adjustments over time.

The anterior pituitary, also known as the adenohypophysis, is the front portion of the pituitary gland. It is responsible for producing and secreting several important hormones that regulate various bodily functions. These hormones include:

* Growth hormone (GH), which stimulates growth and cell reproduction in bones and other tissues.
* Thyroid-stimulating hormone (TSH), which regulates the production of thyroid hormones by the thyroid gland.
* Adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to produce cortisol and other steroid hormones.
* Follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which regulate reproductive function in both males and females by controlling the development and release of eggs or sperm.
* Prolactin, which stimulates milk production in pregnant and nursing women.
* Melanocyte-stimulating hormone (MSH), which regulates skin pigmentation and appetite.

The anterior pituitary gland is controlled by the hypothalamus, a small region of the brain located just above it. The hypothalamus produces releasing and inhibiting hormones that regulate the secretion of hormones from the anterior pituitary. These hormones are released into a network of blood vessels called the portal system, which carries them directly to the anterior pituitary gland.

Damage or disease of the anterior pituitary can lead to hormonal imbalances and various medical conditions, such as growth disorders, thyroid dysfunction, adrenal insufficiency, reproductive problems, and diabetes insipidus.

Prolactin is a hormone produced by the pituitary gland, a small gland located at the base of the brain. Its primary function is to stimulate milk production in women after childbirth, a process known as lactation. However, prolactin also plays other roles in the body, including regulating immune responses, metabolism, and behavior. In men, prolactin helps maintain the sexual glands and contributes to paternal behaviors.

Prolactin levels are usually low in both men and non-pregnant women but increase significantly during pregnancy and after childbirth. Various factors can affect prolactin levels, including stress, sleep, exercise, and certain medications. High prolactin levels can lead to medical conditions such as amenorrhea (absence of menstruation), galactorrhea (spontaneous milk production not related to childbirth), infertility, and reduced sexual desire in both men and women.

Pituitary diseases refer to a group of conditions that affect the pituitary gland, a small endocrine gland located at the base of the brain. The pituitary gland is responsible for producing and secreting several important hormones that regulate various bodily functions, including growth and development, metabolism, stress response, and reproduction.

Pituitary diseases can be classified into two main categories:

1. Pituitary tumors: These are abnormal growths in or around the pituitary gland that can affect its function. Pituitary tumors can be benign (non-cancerous) or malignant (cancerous), and they can vary in size. Some pituitary tumors produce excess hormones, leading to a variety of symptoms, while others may not produce any hormones but can still cause problems by compressing nearby structures in the brain.
2. Pituitary gland dysfunction: This refers to conditions that affect the normal function of the pituitary gland without the presence of a tumor. Examples include hypopituitarism, which is a condition characterized by decreased production of one or more pituitary hormones, and Sheehan's syndrome, which occurs when the pituitary gland is damaged due to severe blood loss during childbirth.

Symptoms of pituitary diseases can vary widely depending on the specific condition and the hormones that are affected. Treatment options may include surgery, radiation therapy, medication, or a combination of these approaches.

Pituitary hormones refer to the chemical messengers produced and released by the pituitary gland, which is a small endocrine gland located at the base of the brain. The pituitary gland is divided into two main parts: the anterior lobe (also known as the adenohypophysis) and the posterior lobe (also known as the neurohypophysis).

Posterior pituitary hormones are those that are produced by the hypothalamus, a region of the brain located above the pituitary gland, and stored in the posterior pituitary before being released. There are two main posterior pituitary hormones:

1. Oxytocin: This hormone plays a role in social bonding, sexual reproduction, and childbirth. During childbirth, oxytocin stimulates uterine contractions to help facilitate delivery of the baby. After delivery, oxytocin continues to be released to stimulate milk production and letdown during breastfeeding.
2. Vasopressin (also known as antidiuretic hormone or ADH): This hormone helps regulate water balance in the body by controlling the amount of urine that is produced by the kidneys. When vasopressin is released, it causes the kidneys to retain water and increase blood volume, which can help to maintain blood pressure.

Together, these posterior pituitary hormones play important roles in regulating various physiological processes in the body.

Luteinizing Hormone (LH) is a glycoprotein hormone, which is primarily produced and released by the anterior pituitary gland. In women, a surge of LH triggers ovulation, the release of an egg from the ovaries during the menstrual cycle. During pregnancy, LH stimulates the corpus luteum to produce progesterone. In men, LH stimulates the testes to produce testosterone. It plays a crucial role in sexual development, reproduction, and maintaining the reproductive system.

Growth Hormone (GH), also known as somatotropin, is a peptide hormone secreted by the somatotroph cells in the anterior pituitary gland. It plays a crucial role in regulating growth, cell reproduction, and regeneration by stimulating the production of another hormone called insulin-like growth factor 1 (IGF-1) in the liver and other tissues. GH also has important metabolic functions, such as increasing glucose levels, enhancing protein synthesis, and reducing fat storage. Its secretion is regulated by two hypothalamic hormones: growth hormone-releasing hormone (GHRH), which stimulates its release, and somatostatin (SRIF), which inhibits its release. Abnormal levels of GH can lead to various medical conditions, such as dwarfism or gigantism if there are deficiencies or excesses, respectively.

Adrenocorticotropic Hormone (ACTH) is a hormone produced and released by the anterior pituitary gland, a small endocrine gland located at the base of the brain. ACTH plays a crucial role in the regulation of the body's stress response and has significant effects on various physiological processes.

The primary function of ACTH is to stimulate the adrenal glands, which are triangular-shaped glands situated on top of the kidneys. The adrenal glands consist of two parts: the outer cortex and the inner medulla. ACTH specifically targets the adrenal cortex, where it binds to specific receptors and initiates a series of biochemical reactions leading to the production and release of steroid hormones, primarily cortisol (a glucocorticoid) and aldosterone (a mineralocorticoid).

Cortisol is involved in various metabolic processes, such as regulating blood sugar levels, modulating the immune response, and helping the body respond to stress. Aldosterone plays a vital role in maintaining electrolyte and fluid balance by promoting sodium reabsorption and potassium excretion in the kidneys.

ACTH release is controlled by the hypothalamus, another part of the brain, which produces corticotropin-releasing hormone (CRH). CRH stimulates the anterior pituitary gland to secrete ACTH, which in turn triggers cortisol production in the adrenal glands. This complex feedback system helps maintain homeostasis and ensures that appropriate amounts of cortisol are released in response to various physiological and psychological stressors.

Disorders related to ACTH can lead to hormonal imbalances, resulting in conditions such as Cushing's syndrome (excessive cortisol production) or Addison's disease (insufficient cortisol production). Proper diagnosis and management of these disorders typically involve assessing the function of the hypothalamic-pituitary-adrenal axis and addressing any underlying issues affecting ACTH secretion.

Human Growth Hormone (HGH), also known as somatotropin, is a peptide hormone produced in the pituitary gland. It plays a crucial role in human development and growth by stimulating the production of another hormone called insulin-like growth factor 1 (IGF-1). IGF-1 promotes the growth and reproduction of cells throughout the body, particularly in bones and other tissues. HGH also helps regulate body composition, body fluids, muscle and bone growth, sugar and fat metabolism, and possibly heart function. It is essential for human development and continues to have important effects throughout life. The secretion of HGH decreases with age, which is thought to contribute to the aging process.

Follicle-Stimulating Hormone (FSH) is a glycoprotein hormone secreted and released by the anterior pituitary gland. In females, it promotes the growth and development of ovarian follicles in the ovary, which ultimately leads to the maturation and release of an egg (ovulation). In males, FSH stimulates the testes to produce sperm. It works in conjunction with luteinizing hormone (LH) to regulate reproductive processes. The secretion of FSH is controlled by the hypothalamic-pituitary-gonadal axis and its release is influenced by the levels of gonadotropin-releasing hormone (GnRH), estrogen, inhibin, and androgens.

Thyrotropin, also known as thyroid-stimulating hormone (TSH), is a hormone secreted by the anterior pituitary gland. Its primary function is to regulate the production and release of thyroxine (T4) and triiodothyronine (T3) hormones from the thyroid gland. Thyrotropin binds to receptors on the surface of thyroid follicular cells, stimulating the uptake of iodide and the synthesis and release of T4 and T3. The secretion of thyrotropin is controlled by the hypothalamic-pituitary-thyroid axis: thyrotropin-releasing hormone (TRH) from the hypothalamus stimulates the release of thyrotropin, while T3 and T4 inhibit its release through a negative feedback mechanism.

Hormones are defined as chemical messengers that are produced by endocrine glands or specialized cells and are transported through the bloodstream to tissues and organs, where they elicit specific responses. They play crucial roles in regulating various physiological processes such as growth, development, metabolism, reproduction, and mood. Examples of hormones include insulin, estrogen, testosterone, adrenaline, and thyroxine.

Pituitary function tests are a group of diagnostic exams that evaluate the proper functioning of the pituitary gland, a small endocrine gland located at the base of the brain. The pituitary gland is responsible for producing and releasing several essential hormones that regulate various bodily functions, including growth, metabolism, stress response, reproduction, and lactation.

These tests typically involve measuring the levels of different hormones in the blood, stimulating or suppressing the pituitary gland with specific medications, and assessing the body's response to these challenges. Some common pituitary function tests include:

1. Growth hormone (GH) testing: Measures GH levels in the blood, often after a provocative test using substances like insulin, arginine, clonidine, or glucagon to stimulate GH release.
2. Thyroid-stimulating hormone (TSH) and free thyroxine (FT4) testing: Assesses the function of the thyroid gland by measuring TSH and FT4 levels in response to TRH (thyrotropin-releasing hormone) stimulation.
3. Adrenocorticotropic hormone (ACTH) and cortisol testing: Evaluates the hypothalamic-pituitary-adrenal axis by measuring ACTH and cortisol levels after a CRH (corticotropin-releasing hormone) stimulation test or an insulin tolerance test.
4. Prolactin (PRL) testing: Measures PRL levels in the blood, which can be elevated due to pituitary tumors or other conditions affecting the hypothalamus.
5. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) testing: Assesses reproductive function by measuring FSH and LH levels, often in conjunction with estradiol or testosterone levels.
6. Gonadotropin-releasing hormone (GnRH) stimulation test: Evaluates gonadal function by measuring FSH and LH levels after GnRH administration.
7. Growth hormone (GH) testing: Measures GH levels in response to various stimuli, such as insulin-like growth factor-1 (IGF-1), glucagon, or arginine.
8. Vasopressin (ADH) testing: Assesses the posterior pituitary function by measuring ADH levels and performing a water deprivation test.

These tests can help diagnose various pituitary disorders, such as hypopituitarism, hyperpituitarism, or pituitary tumors, and guide appropriate treatment strategies.

Pituitary dwarfism, also known as growth hormone deficiency dwarfism or hypopituitarism dwarfism, is a type of dwarfism that results from insufficient production of growth hormone by the pituitary gland during childhood. The medical term for this condition is "growth hormone deficiency."

The pituitary gland is a small gland located at the base of the brain that produces several important hormones, including growth hormone. Growth hormone plays a critical role in regulating growth and development during childhood and adolescence. When the pituitary gland fails to produce enough growth hormone, children do not grow and develop normally, resulting in short stature and other symptoms associated with dwarfism.

Pituitary dwarfism can be caused by a variety of factors, including genetic mutations, brain tumors, trauma, or infection. In some cases, the cause may be unknown. Symptoms of pituitary dwarfism include short stature, delayed puberty, and other hormonal imbalances.

Treatment for pituitary dwarfism typically involves replacing the missing growth hormone with injections of synthetic growth hormone. This therapy can help promote normal growth and development, although it may not completely eliminate the short stature associated with the condition. Early diagnosis and treatment are essential to optimize outcomes and improve quality of life for individuals with pituitary dwarfism.

Hypophysectomy is a surgical procedure that involves the removal or partial removal of the pituitary gland, also known as the hypophysis. The pituitary gland is a small endocrine gland located at the base of the brain, just above the nasal cavity, and is responsible for producing and secreting several important hormones that regulate various bodily functions.

Hypophysectomy may be performed for therapeutic or diagnostic purposes. In some cases, it may be used to treat pituitary tumors or other conditions that affect the function of the pituitary gland. It may also be performed as a research procedure in animal models to study the effects of pituitary hormone deficiency on various physiological processes.

The surgical approach for hypophysectomy may vary depending on the specific indication and the patient's individual anatomy. In general, however, the procedure involves making an incision in the skull and exposing the pituitary gland through a small opening in the bone. The gland is then carefully dissected and removed or partially removed as necessary.

Potential complications of hypophysectomy include damage to surrounding structures such as the optic nerves, which can lead to vision loss, and cerebrospinal fluid leaks. Additionally, removal of the pituitary gland can result in hormonal imbalances that may require long-term management with hormone replacement therapy.

Pituitary hormone release inhibiting hormones, also known as release-inhibiting hormones or hypothalamic inhibitory hormones, are chemical messengers that are produced by the hypothalamus and travel to the pituitary gland through the hypophyseal portal system. They regulate the secretion and release of various anterior pituitary hormones by inhibiting their synthesis and/or release.

The two main types of pituitary hormone release inhibiting hormones are:

1. Somatostatin (also known as growth hormone-inhibiting hormone or GHIH): This hormone inhibits the release of growth hormone (GH) and thyroid-stimulating hormone (TSH) from the anterior pituitary gland.
2. Dopamine: This neurotransmitter also functions as a prolactin-inhibiting hormone (PIH), which inhibits the synthesis and release of prolactin from the anterior pituitary gland.

These hormones play an essential role in maintaining the homeostasis of various physiological processes, including growth, metabolism, lactation, and reproductive functions.

Gonadotropin-Releasing Hormone (GnRH), also known as Luteinizing Hormone-Releasing Hormone (LHRH), is a hormonal peptide consisting of 10 amino acids. It is produced and released by the hypothalamus, an area in the brain that links the nervous system to the endocrine system via the pituitary gland.

GnRH plays a crucial role in regulating reproduction and sexual development through its control of two gonadotropins: follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These gonadotropins, in turn, stimulate the gonads (ovaries or testes) to produce sex steroids and eggs or sperm.

GnRH acts on the anterior pituitary gland by binding to its specific receptors, leading to the release of FSH and LH. The hypothalamic-pituitary-gonadal axis is under negative feedback control, meaning that when sex steroid levels are high, they inhibit the release of GnRH, which subsequently decreases FSH and LH secretion.

GnRH agonists and antagonists have clinical applications in various medical conditions, such as infertility treatments, precocious puberty, endometriosis, uterine fibroids, prostate cancer, and hormone-responsive breast cancer.

Gonadotropins are hormones produced and released by the anterior pituitary gland, a small endocrine gland located at the base of the brain. These hormones play crucial roles in regulating reproduction and sexual development. There are two main types of gonadotropins:

1. Follicle-Stimulating Hormone (FSH): FSH is essential for the growth and development of follicles in the ovaries (in females) or sperm production in the testes (in males). In females, FSH stimulates the maturation of eggs within the follicles.
2. Luteinizing Hormone (LH): LH triggers ovulation in females, causing the release of a mature egg from the dominant follicle. In males, LH stimulates the production and secretion of testosterone in the testes.

Together, FSH and LH work synergistically to regulate various aspects of reproductive function and sexual development. Their secretion is controlled by the hypothalamus, which releases gonadotropin-releasing hormone (GnRH) to stimulate the production and release of FSH and LH from the anterior pituitary gland.

Abnormal levels of gonadotropins can lead to various reproductive disorders, such as infertility or menstrual irregularities in females and issues related to sexual development or function in both sexes. In some cases, synthetic forms of gonadotropins may be used clinically to treat these conditions or for assisted reproductive technologies (ART).

An adenoma is a benign (noncancerous) tumor that develops from glandular epithelial cells. These types of cells are responsible for producing and releasing fluids, such as hormones or digestive enzymes, into the surrounding tissues. Adenomas can occur in various organs and glands throughout the body, including the thyroid, pituitary, adrenal, and digestive systems.

Depending on their location, adenomas may cause different symptoms or remain asymptomatic. Some common examples of adenomas include:

1. Colorectal adenoma (also known as a polyp): These growths occur in the lining of the colon or rectum and can develop into colorectal cancer if left untreated. Regular screenings, such as colonoscopies, are essential for early detection and removal of these polyps.
2. Thyroid adenoma: This type of adenoma affects the thyroid gland and may result in an overproduction or underproduction of hormones, leading to conditions like hyperthyroidism (overactive thyroid) or hypothyroidism (underactive thyroid).
3. Pituitary adenoma: These growths occur in the pituitary gland, which is located at the base of the brain and controls various hormonal functions. Depending on their size and location, pituitary adenomas can cause vision problems, headaches, or hormonal imbalances that affect growth, reproduction, and metabolism.
4. Liver adenoma: These rare benign tumors develop in the liver and may not cause any symptoms unless they become large enough to press on surrounding organs or structures. In some cases, liver adenomas can rupture and cause internal bleeding.
5. Adrenal adenoma: These growths occur in the adrenal glands, which are located above the kidneys and produce hormones that regulate stress responses, metabolism, and blood pressure. Most adrenal adenomas are nonfunctioning, meaning they do not secrete excess hormones. However, functioning adrenal adenomas can lead to conditions like Cushing's syndrome or Conn's syndrome, depending on the type of hormone being overproduced.

It is essential to monitor and manage benign tumors like adenomas to prevent potential complications, such as rupture, bleeding, or hormonal imbalances. Treatment options may include surveillance with imaging studies, medication to manage hormonal issues, or surgical removal of the tumor in certain cases.

The posterior pituitary gland, also known as the neurohypophysis, is the posterior portion of the pituitary gland. It is primarily composed of nerve fibers that originate from the hypothalamus, a region of the brain. These nerve fibers release two important hormones: oxytocin and vasopressin (also known as antidiuretic hormone or ADH).

Oxytocin plays a role in social bonding, sexual reproduction, and childbirth. During childbirth, it stimulates uterine contractions to help facilitate delivery, and after birth, it helps to trigger the release of milk from the mother's breasts during breastfeeding.

Vasopressin, on the other hand, helps regulate water balance in the body by controlling the amount of water that is excreted by the kidneys. It does this by increasing the reabsorption of water in the collecting ducts of the kidney, which leads to a more concentrated urine and helps prevent dehydration.

Overall, the posterior pituitary gland plays a critical role in maintaining fluid balance, social bonding, and reproduction.

Thyroid hormones are hormones produced and released by the thyroid gland, a small endocrine gland located in the neck that helps regulate metabolism, growth, and development in the human body. The two main thyroid hormones are triiodothyronine (T3) and thyroxine (T4), which contain iodine atoms. These hormones play a crucial role in various bodily functions, including heart rate, body temperature, digestion, and brain development. They help regulate the rate at which your body uses energy, affects how sensitive your body is to other hormones, and plays a vital role in the development and differentiation of all cells of the human body. Thyroid hormone levels are regulated by the hypothalamus and pituitary gland through a feedback mechanism that helps maintain proper balance.

Thyrotropin-Releasing Hormone (TRH) is a tripeptide hormone that is produced and released by the hypothalamus in the brain. Its main function is to regulate the release of thyroid-stimulating hormone (TSH) from the anterior pituitary gland. TRH acts on the pituitary gland to stimulate the synthesis and secretion of TSH, which then stimulates the thyroid gland to produce and release thyroid hormones (triiodothyronine (T3) and thyroxine (T4)) into the bloodstream.

TRH is a tripeptide amino acid sequence with the structure of pGlu-His-Pro-NH2, and it is synthesized as a larger precursor molecule called preprothyrotropin-releasing hormone (preproTRH) in the hypothalamus. PreproTRH undergoes post-translational processing to produce TRH, which is then stored in secretory vesicles and released into the hypophyseal portal system, where it travels to the anterior pituitary gland and binds to TRH receptors on thyrotroph cells.

In addition to its role in regulating TSH release, TRH has been shown to have other physiological functions, including modulation of feeding behavior, body temperature, and neurotransmitter release. Dysregulation of the TRH-TSH axis can lead to various thyroid disorders, such as hypothyroidism or hyperthyroidism.

A prolactinoma is a type of pituitary tumor that produces an excess amount of the hormone prolactin, leading to various symptoms. The pituitary gland, located at the base of the brain, is responsible for producing and releasing several hormones that regulate different bodily functions. Prolactin is one such hormone, primarily known for its role in stimulating milk production in women during lactation (breastfeeding).

Prolactinoma tumors can be classified into two types: microprolactinomas and macroprolactinomas. Microprolactinomas are smaller tumors, typically less than 10 millimeters in size, while macroprolactinomas are larger tumors, generally greater than 10 millimeters in size.

The overproduction of prolactin caused by these tumors can lead to several clinical manifestations, including:

1. Galactorrhea: Unusual and often spontaneous milk production or leakage from the nipples, which can occur in both men and women who do not have a recent history of pregnancy or breastfeeding.
2. Menstrual irregularities: In women, high prolactin levels can interfere with the normal functioning of other hormones, leading to menstrual irregularities such as infrequent periods (oligomenorrhea) or absent periods (amenorrhea), and sometimes infertility.
3. Sexual dysfunction: In both men and women, high prolactin levels can cause decreased libido and sexual desire. Men may also experience erectile dysfunction and reduced sperm production.
4. Bone loss: Over time, high prolactin levels can lead to decreased bone density and an increased risk of osteoporosis due to the disruption of other hormones that regulate bone health.
5. Headaches and visual disturbances: As the tumor grows, it may put pressure on surrounding structures in the brain, leading to headaches and potential vision problems such as blurred vision or decreased peripheral vision.

Diagnosis typically involves measuring prolactin levels in the blood and performing imaging tests like an MRI (magnetic resonance imaging) scan to assess the size of the tumor. Treatment usually consists of medication to lower prolactin levels, such as dopamine agonists (e.g., bromocriptine or cabergoline), which can also help shrink the tumor. In some cases, surgery may be necessary if medication is ineffective or if the tumor is large and causing severe symptoms.

Pituitary apoplexy is a medical emergency that involves bleeding into the pituitary gland (a small gland at the base of the brain) and/or sudden swelling of the pituitary gland. This can lead to compression of nearby structures, such as the optic nerves and the hypothalamus, causing symptoms like severe headache, visual disturbances, hormonal imbalances, and altered mental status. It is often associated with a pre-existing pituitary tumor (such as a pituitary adenoma), but can also occur in individuals without any known pituitary abnormalities. Immediate medical attention is required to manage this condition, which may include surgical intervention, hormone replacement therapy, and supportive care.

Growth Hormone-Releasing Hormone (GHRH) is a hormone that is produced and released by the hypothalamus, a small gland located in the brain. Its primary function is to stimulate the anterior pituitary gland to release growth hormone (GH) into the bloodstream. GH plays a crucial role in growth and development, particularly during childhood and adolescence, by promoting the growth of bones and muscles.

GHRH is a 44-amino acid peptide that binds to specific receptors on the surface of pituitary cells, triggering a series of intracellular signals that ultimately lead to the release of GH. The production and release of GHRH are regulated by various factors, including sleep, stress, exercise, and nutrition.

Abnormalities in the production or function of GHRH can lead to growth disorders, such as dwarfism or gigantism, as well as other hormonal imbalances. Therefore, understanding the role of GHRH in regulating GH release is essential for diagnosing and treating these conditions.

Transcription Factor Pit-1, also known as POU1F1 or pituitary-specific transcription factor 1, is a protein that plays a crucial role in the development and function of the anterior pituitary gland. It is a member of the POU domain family of transcription factors, which are characterized by a conserved DNA-binding domain.

Pit-1 is essential for the differentiation and proliferation of certain types of pituitary cells, including those that produce growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH). Pit-1 binds to specific DNA sequences in the promoter regions of these hormone genes, thereby activating their transcription and promoting hormone production.

Mutations in the gene encoding Pit-1 can lead to a variety of pituitary disorders, such as dwarfism due to GH deficiency, delayed puberty, and hypothyroidism due to TSH deficiency. Additionally, some studies have suggested that Pit-1 may also play a role in regulating energy balance and body weight, although the exact mechanisms are not fully understood.

Pro-opiomelanocortin (POMC) is a precursor protein that gets cleaved into several biologically active peptides in the body. These peptides include adrenocorticotropic hormone (ACTH), beta-lipotropin, and multiple opioid peptides such as beta-endorphin, met-enkephalin, and leu-enkephalin.

ACTH stimulates the release of cortisol from the adrenal gland, while beta-lipotropin has various metabolic functions. The opioid peptides derived from POMC have pain-relieving (analgesic) and rewarding effects in the brain. Dysregulation of the POMC system has been implicated in several medical conditions, including obesity, addiction, and certain types of hormone deficiencies.

A basophilic adenoma is a rare type of benign tumor that arises from the glandular cells of an endocrine gland, specifically the cells that produce and store hormones. The term "basophilic" refers to the appearance of the tumor cells under a microscope, which have a high affinity for basic dyes due to their rich content of ribonucleic acid (RNA).

Basophilic adenomas are most commonly found in the pituitary gland, a small endocrine gland located at the base of the brain. These tumors can produce and secrete excessive amounts of hormones, leading to various clinical symptoms depending on the type of hormone involved. The most common types of basophilic adenomas are prolactinomas, which secrete high levels of the hormone prolactin, and growth hormone-secreting adenomas, which produce excessive amounts of growth hormone.

Treatment for basophilic adenomas typically involves surgical removal of the tumor, followed by radiation therapy or medical management with drugs that suppress hormone production. The prognosis for patients with basophilic adenomas is generally good, with most individuals experiencing a significant improvement in symptoms and quality of life following treatment. However, regular follow-up care is necessary to monitor for recurrence and manage any residual hormonal imbalances.

Pituitary hormone-releasing hormones (PRHs), also known as hypothalamic releasing hormones or hypothalamic hormones, are small neuropeptides produced and released by the hypothalamus - a small region of the brain. These hormones play crucial roles in regulating the secretion and release of various pituitary hormones, which in turn control several essential bodily functions, including growth, development, metabolism, stress response, reproduction, and lactation.

There are several PRHs, each with a specific target pituitary hormone:

1. Thyrotropin-releasing hormone (TRH): Stimulates the release of thyroid-stimulating hormone (TSH) from the anterior pituitary gland, which then promotes the production and release of thyroid hormones.
2. Gonadotropin-releasing hormone (GnRH): Regulates the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary gland, which are essential for reproductive functions.
3. Corticotropin-releasing hormone (CRH): Stimulates the release of adrenocorticotropic hormone (ACTH) from the anterior pituitary gland, which then promotes the production and release of cortisol and other glucocorticoids from the adrenal glands.
4. Growth hormone-releasing hormone (GHRH): Stimulates the release of growth hormone (GH) from the anterior pituitary gland, which is essential for growth, development, and metabolism regulation.
5. Somatostatin or growth hormone-inhibiting hormone (GHIH): Inhibits the release of GH from the anterior pituitary gland and also suppresses the secretion of thyroid hormones.
6. Prolactin-releasing hormone (PRH) or prolactin-releasing factor (PRF): Stimulates the release of prolactin from the anterior pituitary gland, which is essential for lactation and reproductive functions.
7. Prolactin-inhibiting hormone (PIH) or dopamine: Inhibits the release of prolactin from the anterior pituitary gland.

These releasing hormones and inhibitory hormones work together to maintain a delicate balance in various physiological processes, including growth, development, metabolism, stress response, and reproductive functions. Dysregulation of these hormonal systems can lead to various endocrine disorders and diseases.

Gonadal steroid hormones, also known as gonadal sex steroids, are hormones that are produced and released by the gonads (i.e., ovaries in women and testes in men). These hormones play a critical role in the development and maintenance of secondary sexual characteristics, reproductive function, and overall health.

The three main classes of gonadal steroid hormones are:

1. Androgens: These are male sex hormones that are primarily produced by the testes but also produced in smaller amounts by the ovaries and adrenal glands. The most well-known androgen is testosterone, which plays a key role in the development of male secondary sexual characteristics such as facial hair, deepening of the voice, and increased muscle mass.
2. Estrogens: These are female sex hormones that are primarily produced by the ovaries but also produced in smaller amounts by the adrenal glands. The most well-known estrogen is estradiol, which plays a key role in the development of female secondary sexual characteristics such as breast development and the menstrual cycle.
3. Progestogens: These are hormones that are produced by the ovaries during the second half of the menstrual cycle and play a key role in preparing the uterus for pregnancy. The most well-known progestogen is progesterone, which also plays a role in maintaining pregnancy and regulating the menstrual cycle.

Gonadal steroid hormones can have significant effects on various physiological processes, including bone density, cognitive function, mood, and sexual behavior. Disorders of gonadal steroid hormone production or action can lead to a range of health problems, including infertility, osteoporosis, and sexual dysfunction.

Follicle-stimulating hormone (FSH) is a glycoprotein hormone produced and released by the anterior pituitary gland. It plays crucial roles in the reproductive system, primarily by promoting the growth and development of follicles in the ovaries or sperm production in the testes.

The FSH molecule consists of two subunits: α (alpha) and β (beta). The α-subunit is common to several glycoprotein hormones, including thyroid-stimulating hormone (TSH), luteinizing hormone (LH), and human chorionic gonadotropin (hCG). In contrast, the β-subunit is unique to each hormone and determines its specific biological activity.

A medical definition of 'Follicle Stimulating Hormone, beta Subunit' refers to the distinct portion of the FSH molecule that is responsible for its particular functions in the body. The β-subunit of FSH enables the hormone to bind to its specific receptors in the gonads and initiate downstream signaling pathways leading to follicular development and spermatogenesis. Any alterations or mutations in the FSH beta subunit can lead to disruptions in reproductive processes, potentially causing infertility or other related disorders.

Septo-Optic Dysplasia (SOD) is a rare disorder that affects the development of the brain, eyes, and pituitary gland. It is also known as De Morsier's syndrome. The condition is characterized by underdevelopment of the optic nerve, which can lead to varying degrees of vision loss, from mild visual impairment to complete blindness.

The septum pellucidum, a part of the brain that separates the two hemispheres, may be absent or poorly formed in individuals with SOD. This can result in a range of neurological symptoms, including developmental delays, intellectual disability, and movement disorders.

Additionally, SOD is often associated with pituitary gland dysfunction, which can lead to hormonal imbalances and growth problems. Treatment for SOD typically involves managing the individual symptoms and may include vision therapy, special education services, and hormone replacement therapy.

Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) is a neuropeptide that belongs to the vasoactive intestinal polypeptide (VIP)/secretin/glucagon family. It was first isolated from the ovine hypothalamus and later found in various tissues and organs throughout the body, including the brain, pituitary gland, and peripheral nerves.

PACAP exists in two forms, PACAP-38 and PACAP-27, which differ in their length but share the same amino acid sequence at the N-terminus. PACAP exerts its effects through specific G protein-coupled receptors, including PAC1, VPAC1, and VPAC2 receptors, which are widely distributed throughout the body.

PACAP has a wide range of biological activities, including neurotrophic, neuroprotective, vasodilatory, and immunomodulatory effects. In the pituitary gland, PACAP stimulates adenylate cyclase activity, leading to an increase in intracellular cAMP levels, which in turn regulates the release of various hormones, including growth hormone, prolactin, and thyroid-stimulating hormone.

Overall, PACAP is a crucial neuropeptide involved in various physiological processes, and its dysregulation has been implicated in several pathological conditions, such as neurodegenerative diseases, mood disorders, and cancer.

Thyroxine (T4) is a type of hormone produced and released by the thyroid gland, a small butterfly-shaped endocrine gland located in the front of your neck. It is one of two major hormones produced by the thyroid gland, with the other being triiodothyronine (T3).

Thyroxine plays a crucial role in regulating various metabolic processes in the body, including growth, development, and energy expenditure. Specifically, T4 helps to control the rate at which your body burns calories for energy, regulates protein, fat, and carbohydrate metabolism, and influences the body's sensitivity to other hormones.

T4 is produced by combining iodine and tyrosine, an amino acid found in many foods. Once produced, T4 circulates in the bloodstream and gets converted into its active form, T3, in various tissues throughout the body. Thyroxine has a longer half-life than T3, which means it remains active in the body for a more extended period.

Abnormal levels of thyroxine can lead to various medical conditions, such as hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid). These conditions can cause a range of symptoms, including weight gain or loss, fatigue, mood changes, and changes in heart rate and blood pressure.

The hypothalamus is a small, vital region of the brain that lies just below the thalamus and forms part of the limbic system. It plays a crucial role in many important functions including:

1. Regulation of body temperature, hunger, thirst, fatigue, sleep, and circadian rhythms.
2. Production and regulation of hormones through its connection with the pituitary gland (the hypophysis). It controls the release of various hormones by producing releasing and inhibiting factors that regulate the anterior pituitary's function.
3. Emotional responses, behavior, and memory formation through its connections with the limbic system structures like the amygdala and hippocampus.
4. Autonomic nervous system regulation, which controls involuntary physiological functions such as heart rate, blood pressure, and digestion.
5. Regulation of the immune system by interacting with the autonomic nervous system.

Damage to the hypothalamus can lead to various disorders like diabetes insipidus, growth hormone deficiency, altered temperature regulation, sleep disturbances, and emotional or behavioral changes.

Hyperprolactinemia is a medical condition characterized by abnormally high levels of prolactin, a hormone produced by the pituitary gland. In women, this can lead to menstrual irregularities, milk production outside of pregnancy (galactorrhea), and infertility. In men, it can cause decreased libido, erectile dysfunction, breast enlargement (gynecomastia), and infertility. The condition can be caused by various factors, including pituitary tumors, certain medications, and hypothyroidism. Treatment typically involves addressing the underlying cause and may include medication to lower prolactin levels.

Hydrocortisone is a synthetic glucocorticoid, which is a class of steroid hormones. It is identical to the naturally occurring cortisol, a hormone produced by the adrenal gland that helps regulate metabolism and helps your body respond to stress. Hydrocortisone has anti-inflammatory effects and is used to treat various inflammatory conditions such as allergies, skin disorders, and autoimmune diseases. It works by suppressing the immune system's response to reduce swelling, redness, itching, and other symptoms caused by inflammation.

Hydrocortisone is available in different forms, including oral tablets, topical creams, lotions, gels, and ointments, as well as injectable solutions. The specific use and dosage depend on the condition being treated and the individual patient's medical history and current health status.

As with any medication, hydrocortisone can have side effects, especially when used in high doses or for extended periods. Common side effects include increased appetite, weight gain, mood changes, insomnia, and skin thinning. Long-term use of hydrocortisone may also increase the risk of developing osteoporosis, diabetes, cataracts, and other health problems. Therefore, it is essential to follow your healthcare provider's instructions carefully when using this medication.

Corticotropin-Releasing Hormone (CRH) is a hormone that is produced and released by the hypothalamus, a small gland located in the brain. CRH plays a critical role in the body's stress response system.

When the body experiences stress, the hypothalamus releases CRH, which then travels to the pituitary gland, another small gland located at the base of the brain. Once there, CRH stimulates the release of adrenocorticotropic hormone (ACTH) from the pituitary gland.

ACTH then travels through the bloodstream to the adrenal glands, which are located on top of the kidneys. ACTH stimulates the adrenal glands to produce and release cortisol, a hormone that helps the body respond to stress by regulating metabolism, immune function, and blood pressure, among other things.

Overall, CRH is an important part of the hypothalamic-pituitary-adrenal (HPA) axis, which regulates many bodily functions related to stress response, mood, and cognition. Dysregulation of the HPA axis and abnormal levels of CRH have been implicated in various psychiatric and medical conditions, including depression, anxiety disorders, post-traumatic stress disorder (PTSD), and Cushing's syndrome.

LIM-homeodomain proteins are a family of transcription factors that contain both LIM domains and homeodomains. LIM domains are cysteine-rich motifs that function in protein-protein interactions, often mediating the formation of multimeric complexes. Homeodomains are DNA-binding domains that recognize and bind to specific DNA sequences, thereby regulating gene transcription.

LIM-homeodomain proteins play important roles in various developmental processes, including cell fate determination, differentiation, and migration. They have been implicated in the regulation of muscle, nerve, and cardiovascular development, as well as in cancer and other diseases. Some examples of LIM-homeodomain proteins include LMX1A, LHX2, and ISL1.

These proteins are characterized by the presence of two LIM domains at the N-terminus and a homeodomain at the C-terminus. The LIM domains are involved in protein-protein interactions, while the homeodomain is responsible for DNA binding and transcriptional regulation. Some LIM-homeodomain proteins also contain other functional domains, such as zinc fingers or leucine zippers, which contribute to their diverse functions.

Overall, LIM-homeodomain proteins are important regulators of gene expression and play critical roles in various developmental and disease processes.

Glycoprotein hormones are a group of hormones that share a similar structure and are made up of four subunits: two identical alpha subunits and two distinct beta subunits. The alpha subunit is common to all glycoprotein hormones, including thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and human chorionic gonadotropin (hCG).

The alpha subunit of glycoprotein hormones is a 92 amino acid polypeptide chain that contains several disulfide bonds, which help to stabilize its structure. It is heavily glycosylated, meaning that it contains many carbohydrate groups attached to the protein backbone. The alpha subunit plays an important role in the biological activity of the hormone by interacting with a specific receptor on the target cell surface.

The alpha subunit contains several regions that are important for its function, including a signal peptide, a variable region, and a conserved region. The signal peptide is a short sequence of amino acids at the N-terminus of the protein that directs it to the endoplasmic reticulum for processing and secretion. The variable region contains several amino acid residues that differ between different glycoprotein hormones, while the conserved region contains amino acids that are identical or very similar in all glycoprotein hormones.

Together with the beta subunit, the alpha subunit forms the functional hormone molecule. The beta subunit determines the specificity of the hormone for its target cells and regulates its biological activity.

The Hypothalamo-Hypophyseal system, also known as the hypothalamic-pituitary system, is a crucial part of the endocrine system that regulates many bodily functions. It consists of two main components: the hypothalamus and the pituitary gland.

The hypothalamus is a region in the brain that receives information from various parts of the body and integrates them to regulate vital functions such as body temperature, hunger, thirst, sleep, and emotional behavior. It also produces and releases neurohormones that control the secretion of hormones from the pituitary gland.

The pituitary gland is a small gland located at the base of the brain, just below the hypothalamus. It consists of two parts: the anterior pituitary (also called adenohypophysis) and the posterior pituitary (also called neurohypophysis). The anterior pituitary produces and releases several hormones that regulate various bodily functions such as growth, metabolism, reproduction, and stress response. The posterior pituitary stores and releases hormones produced by the hypothalamus, including antidiuretic hormone (ADH) and oxytocin.

The hypothalamo-hypophyseal system works together to maintain homeostasis in the body by regulating various physiological processes through hormonal signaling. Dysfunction of this system can lead to several endocrine disorders, such as diabetes insipidus, pituitary tumors, and hypothalamic-pituitary axis disorders.

Parathyroid hormone (PTH) is a polypeptide hormone that plays a crucial role in the regulation of calcium and phosphate levels in the body. It is produced and secreted by the parathyroid glands, which are four small endocrine glands located on the back surface of the thyroid gland.

The primary function of PTH is to maintain normal calcium levels in the blood by increasing calcium absorption from the gut, mobilizing calcium from bones, and decreasing calcium excretion by the kidneys. PTH also increases phosphate excretion by the kidneys, which helps to lower serum phosphate levels.

In addition to its role in calcium and phosphate homeostasis, PTH has been shown to have anabolic effects on bone tissue, stimulating bone formation and preventing bone loss. However, chronic elevations in PTH levels can lead to excessive bone resorption and osteoporosis.

Overall, Parathyroid Hormone is a critical hormone that helps maintain mineral homeostasis and supports healthy bone metabolism.

A craniopharyngioma is a type of brain tumor that develops near the pituitary gland, which is a small gland located at the base of the brain. These tumors arise from remnants of Rathke's pouch, an embryonic structure involved in the development of the pituitary gland.

Craniopharyngiomas are typically slow-growing and benign (non-cancerous), but they can still cause significant health problems due to their location. They can compress nearby structures such as the optic nerves, hypothalamus, and pituitary gland, leading to symptoms like vision loss, hormonal imbalances, and cognitive impairment.

Treatment for craniopharyngiomas usually involves surgical removal of the tumor, followed by radiation therapy in some cases. Regular follow-up with a healthcare team is essential to monitor for recurrence and manage any long-term effects of treatment.

The Sella Turcica, also known as the Turkish saddle, is a depression or fossa in the sphenoid bone located at the base of the skull. It forms a housing for the pituitary gland, which is a small endocrine gland often referred to as the "master gland" because it controls other glands and makes several essential hormones. The Sella Turcica has a saddle-like shape, with its anterior and posterior clinoids forming the front and back of the saddle, respectively. This region is of significant interest in neuroimaging and clinical settings, as various conditions such as pituitary tumors or other abnormalities may affect the size, shape, and integrity of the Sella Turcica.

Estradiol is a type of estrogen, which is a female sex hormone. It is the most potent and dominant form of estrogen in humans. Estradiol plays a crucial role in the development and maintenance of secondary sexual characteristics in women, such as breast development and regulation of the menstrual cycle. It also helps maintain bone density, protect the lining of the uterus, and is involved in cognition and mood regulation.

Estradiol is produced primarily by the ovaries, but it can also be synthesized in smaller amounts by the adrenal glands and fat cells. In men, estradiol is produced from testosterone through a process called aromatization. Abnormal levels of estradiol can contribute to various health issues, such as hormonal imbalances, infertility, osteoporosis, and certain types of cancer.

Radioimmunoassay (RIA) is a highly sensitive analytical technique used in clinical and research laboratories to measure concentrations of various substances, such as hormones, vitamins, drugs, or tumor markers, in biological samples like blood, urine, or tissues. The method relies on the specific interaction between an antibody and its corresponding antigen, combined with the use of radioisotopes to quantify the amount of bound antigen.

In a typical RIA procedure, a known quantity of a radiolabeled antigen (also called tracer) is added to a sample containing an unknown concentration of the same unlabeled antigen. The mixture is then incubated with a specific antibody that binds to the antigen. During the incubation period, the antibody forms complexes with both the radiolabeled and unlabeled antigens.

After the incubation, the unbound (free) radiolabeled antigen is separated from the antibody-antigen complexes, usually through a precipitation or separation step involving centrifugation, filtration, or chromatography. The amount of radioactivity in the pellet (containing the antibody-antigen complexes) is then measured using a gamma counter or other suitable radiation detection device.

The concentration of the unlabeled antigen in the sample can be determined by comparing the ratio of bound to free radiolabeled antigen in the sample to a standard curve generated from known concentrations of unlabeled antigen and their corresponding bound/free ratios. The higher the concentration of unlabeled antigen in the sample, the lower the amount of radiolabeled antigen that will bind to the antibody, resulting in a lower bound/free ratio.

Radioimmunoassays offer high sensitivity, specificity, and accuracy, making them valuable tools for detecting and quantifying low levels of various substances in biological samples. However, due to concerns about radiation safety and waste disposal, alternative non-isotopic immunoassay techniques like enzyme-linked immunosorbent assays (ELISAs) have become more popular in recent years.

Testosterone is a steroid hormone that belongs to androsten class of hormones. It is primarily secreted by the Leydig cells in the testes of males and, to a lesser extent, by the ovaries and adrenal glands in females. Testosterone is the main male sex hormone and anabolic steroid. It plays a key role in the development of masculine characteristics, such as body hair and muscle mass, and contributes to bone density, fat distribution, red cell production, and sex drive. In females, testosterone contributes to sexual desire and bone health. Testosterone is synthesized from cholesterol and its production is regulated by luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

Adrenal insufficiency is a condition in which the adrenal glands do not produce adequate amounts of certain hormones, primarily cortisol and aldosterone. Cortisol helps regulate metabolism, respond to stress, and suppress inflammation, while aldosterone helps regulate sodium and potassium levels in the body to maintain blood pressure.

Primary adrenal insufficiency, also known as Addison's disease, occurs when there is damage to the adrenal glands themselves, often due to autoimmune disorders, infections, or certain medications. Secondary adrenal insufficiency occurs when the pituitary gland fails to produce enough adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to produce cortisol.

Symptoms of adrenal insufficiency may include fatigue, weakness, weight loss, decreased appetite, nausea, vomiting, diarrhea, abdominal pain, low blood pressure, dizziness, and darkening of the skin. Treatment typically involves replacing the missing hormones with medications taken orally or by injection.

An adenoma is a benign tumor that forms in glandular tissue. When referring to "acidophil," it describes the appearance of the cells under a microscope. Acidophils are cells that take up acidic dyes, giving them a distinct appearance. In the context of an adenoma, an acidophil adenoma would be a benign tumor composed of acidophil cells.

Acidophil adenomas are most commonly found in the pituitary gland and are also known as lactotroph or mammosomatotroph adenomas. These tumors can produce and release prolactin, growth hormone, or both, leading to various endocrine disorders such as hyperprolactinemia, acromegaly, or gigantism. Treatment options typically include surgical removal of the tumor or medical management with dopamine agonists or somatostatin analogs.

Central nervous system (CNS) cysts are abnormal fluid-filled sacs that develop in the brain or spinal cord. These cysts can be congenital, meaning they are present at birth and develop as a result of abnormal embryonic development, or they can be acquired later in life due to injury, infection, or disease.

CNS cysts can vary in size and may cause symptoms depending on their location and the amount of pressure they place on surrounding brain or spinal cord tissue. Symptoms may include headaches, seizures, weakness, numbness, or difficulty with coordination and balance. In some cases, CNS cysts may not cause any symptoms and may be discovered incidentally during imaging studies performed for other reasons.

There are several types of CNS cysts, including:

1. Arachnoid cysts: These are the most common type of CNS cyst and occur between the layers of the arachnoid membrane that covers the brain and spinal cord.
2. Colloid cysts: These cysts typically develop at the junction of the third and fourth ventricles in the brain and can obstruct the flow of cerebrospinal fluid (CSF), leading to increased intracranial pressure.
3. Ependymal cysts: These cysts arise from the ependymal cells that line the ventricular system of the brain and can cause symptoms by compressing surrounding brain tissue.
4. Neuroglial cysts: These cysts are composed of glial cells, which support and protect nerve cells in the CNS.
5. Pineal cysts: These cysts develop in the pineal gland, a small endocrine gland located near the center of the brain.

Treatment for CNS cysts depends on their size, location, and symptoms. In some cases, observation and monitoring may be all that is necessary. However, if the cyst is causing significant symptoms or is at risk of rupturing or obstructing CSF flow, surgical intervention may be required to remove or reduce the size of the cyst.

Hypogonadism is a medical condition characterized by the inability of the gonads (testes in males and ovaries in females) to produce sufficient amounts of sex hormones, such as testosterone and estrogen. This can lead to various symptoms including decreased libido, erectile dysfunction in men, irregular menstrual periods in women, and reduced fertility in both sexes. Hypogonadism may be caused by genetic factors, aging, injury to the gonads, or certain medical conditions such as pituitary disorders. It can be treated with hormone replacement therapy.

Hormone Replacement Therapy (HRT) is a medical treatment that involves the use of hormones to replace or supplement those that the body is no longer producing or no longer producing in sufficient quantities. It is most commonly used to help manage symptoms associated with menopause and conditions related to hormonal imbalances.

In women, HRT typically involves the use of estrogen and/or progesterone to alleviate hot flashes, night sweats, vaginal dryness, and mood changes that can occur during menopause. In some cases, testosterone may also be prescribed to help improve energy levels, sex drive, and overall sense of well-being.

In men, HRT is often used to treat low testosterone levels (hypogonadism) and related symptoms such as fatigue, decreased muscle mass, and reduced sex drive.

It's important to note that while HRT can be effective in managing certain symptoms, it also carries potential risks, including an increased risk of blood clots, stroke, breast cancer (in women), and cardiovascular disease. Therefore, the decision to undergo HRT should be made carefully and discussed thoroughly with a healthcare provider.

Neurogenic diabetes insipidus is a condition characterized by the production of large amounts of dilute urine (polyuria) and increased thirst (polydipsia) due to deficiency of antidiuretic hormone (ADH), also known as vasopressin, which is produced by the hypothalamus and stored in the posterior pituitary gland.

Neurogenic diabetes insipidus can occur when there is damage to the hypothalamus or pituitary gland, leading to a decrease in ADH production or release. Causes of neurogenic diabetes insipidus include brain tumors, head trauma, surgery, meningitis, encephalitis, and autoimmune disorders.

In this condition, the kidneys are unable to reabsorb water from the urine due to the lack of ADH, resulting in the production of large volumes of dilute urine. This can lead to dehydration, electrolyte imbalances, and other complications if not properly managed. Treatment typically involves replacing the missing ADH with a synthetic hormone called desmopressin, which can be administered as a nasal spray, oral tablet, or injection.

The endocrine system is a complex network of glands and organs that produce, store, and secrete hormones. It plays a crucial role in regulating various functions in the body, including metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood.

Endocrine system diseases or disorders occur when there is a problem with the production or regulation of hormones. This can result from:

1. Overproduction or underproduction of hormones by the endocrine glands.
2. Impaired response of target cells to hormones.
3. Disruption in the feedback mechanisms that regulate hormone production.

Examples of endocrine system diseases include:

1. Diabetes Mellitus - a group of metabolic disorders characterized by high blood sugar levels due to insulin deficiency or resistance.
2. Hypothyroidism - underactive thyroid gland leading to slow metabolism, weight gain, fatigue, and depression.
3. Hyperthyroidism - overactive thyroid gland causing rapid heartbeat, anxiety, weight loss, and heat intolerance.
4. Cushing's Syndrome - excess cortisol production resulting in obesity, high blood pressure, and weak muscles.
5. Addison's Disease - insufficient adrenal hormone production leading to weakness, fatigue, and low blood pressure.
6. Acromegaly - overproduction of growth hormone after puberty causing enlargement of bones, organs, and soft tissues.
7. Gigantism - similar to acromegaly but occurs before puberty resulting in excessive height and body size.
8. Hypopituitarism - underactive pituitary gland leading to deficiencies in various hormones.
9. Hyperparathyroidism - overactivity of the parathyroid glands causing calcium imbalances and kidney stones.
10. Precocious Puberty - early onset of puberty due to premature activation of the pituitary gland.

Treatment for endocrine system diseases varies depending on the specific disorder and may involve medication, surgery, lifestyle changes, or a combination of these approaches.

Hypothyroidism is a medical condition where the thyroid gland, which is a small butterfly-shaped gland located in the front of your neck, does not produce enough thyroid hormones. This results in a slowing down of the body's metabolic processes, leading to various symptoms such as fatigue, weight gain, constipation, cold intolerance, dry skin, hair loss, muscle weakness, and depression.

The two main thyroid hormones produced by the thyroid gland are triiodothyronine (T3) and thyroxine (T4). These hormones play crucial roles in regulating various bodily functions, including heart rate, body temperature, and energy levels. In hypothyroidism, the production of these hormones is insufficient, leading to a range of symptoms that can affect multiple organ systems.

Hypothyroidism can be caused by several factors, including autoimmune disorders (such as Hashimoto's thyroiditis), surgical removal of the thyroid gland, radiation therapy for neck cancer, certain medications, and congenital defects. Hypothyroidism is typically diagnosed through blood tests that measure levels of TSH (thyroid-stimulating hormone), T3, and T4. Treatment usually involves taking synthetic thyroid hormones to replace the missing hormones and alleviate symptoms.

Pituitary hormone receptors are specialized protein molecules found on the surface of target cells in various organs and tissues throughout the body. These receptors selectively bind to specific pituitary hormones, which are released from the pituitary gland, a small endocrine gland located at the base of the brain. The binding of the hormone to its corresponding receptor triggers a series of intracellular signaling events that ultimately lead to physiological responses in the target cells.

There are several types of pituitary hormones, each with its own unique receptors, including:

1. Growth Hormone (GH) Receptors: These receptors are found on many tissues, such as liver, muscle, and bone. The binding of GH to these receptors stimulates the production of insulin-like growth factor 1 (IGF-1), which promotes cell growth and division, as well as other metabolic processes.
2. Adrenocorticotropic Hormone (ACTH) Receptors: These receptors are primarily located on cells in the adrenal gland, particularly in the adrenal cortex. The binding of ACTH to these receptors stimulates the production and release of cortisol, a steroid hormone involved in stress response, metabolism, and immune function.
3. Thyroid-Stimulating Hormone (TSH) Receptors: These receptors are found on the surface of thyroid follicular cells. The binding of TSH to these receptors triggers the production and release of thyroid hormones, triiodothyronine (T3) and thyroxine (T4), which regulate metabolism, growth, and development.
4. Follicle-Stimulating Hormone (FSH) Receptors: These receptors are present in the gonads (ovaries and testes). In females, FSH binds to these receptors to stimulate follicular growth and estrogen production, while in males, it promotes spermatogenesis.
5. Luteinizing Hormone (LH) Receptors: These receptors are also found in the gonads. In females, LH binding triggers ovulation and progesterone production, while in males, it stimulates testosterone production and sperm maturation.
6. Prolactin (PRL) Receptors: These receptors are located in various tissues, including the mammary glands, liver, and brain. The binding of PRL to these receptors promotes lactation, growth, and differentiation of mammary cells, as well as modulating immune function and behavior.
7. Melanocyte-Stimulating Hormone (MSH) Receptors: These receptors are found in the skin and central nervous system. The binding of MSH to these receptors regulates pigmentation, appetite, and energy balance.
8. Growth Hormone-Releasing Hormone (GHRH) Receptors: These receptors are present in the pituitary gland. The binding of GHRH to these receptors stimulates the release of growth hormone, which promotes growth, cell reproduction, and regeneration.
9. Somatostatin Receptors (SST): These receptors are located in various tissues, including the pancreas, brain, and gastrointestinal tract. The binding of somatostatin to these receptors inhibits the release of several hormones, such as growth hormone, insulin, and glucagon.
10. Corticotropin-Releasing Hormone (CRH) Receptors: These receptors are found in the hypothalamus and other brain regions. The binding of CRH to these receptors stimulates the release of adrenocorticotropic hormone (ACTH), which regulates stress response, metabolism, and immune function.
11. Thyrotropin-Releasing Hormone (TRH) Receptors: These receptors are present in the hypothalamus and pituitary gland. The binding of TRH to these receptors stimulates the release of thyroid-stimulating hormone (TSH), which regulates thyroid function and metabolism.
12. Gonadotropin-Releasing Hormone (GnRH) Receptors: These receptors are located in the hypothalamus and pituitary gland. The binding of GnRH to these receptors stimulates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which regulate reproductive function.
13. Prolactin-Releasing Hormone (PRH) Receptors: These receptors are found in the hypothalamus and pituitary gland. The binding of PRH to these receptors stimulates the release of prolactin, which regulates lactation and other physiological processes.
14. Growth Hormone-Releasing Hormone (GHRH) Receptors: These receptors are located in the hypothalamus and pituitary gland. The binding of GHRH to these receptors stimulates the release of growth hormone, which regulates growth, metabolism, and other physiological processes.
15. Melanin-Concentrating Hormone (MCH) Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of MCH to these receptors regulates energy balance, feeding behavior, and sleep-wake cycles.
16. Neuropeptide Y (NPY) Receptors: These receptors are located in various brain regions and peripheral tissues. The binding of NPY to these receptors regulates energy balance, feeding behavior, stress response, and cardiovascular function.
17. Corticotropin-Releasing Hormone (CRH) Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of CRH to these receptors regulates the hypothalamic-pituitary-adrenal axis, stress response, and anxiety.
18. Oxytocin Receptors: These receptors are located in various brain regions and peripheral tissues. The binding of oxytocin to these receptors regulates social behavior, maternal care, and reproductive function.
19. Vasopressin Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of vasopressin to these receptors regulates water balance, blood pressure, and social behavior.
20. Substance P Receptors (Neurokinin 1 Receptors): These receptors are located in various brain regions and peripheral tissues. The binding of substance P to these receptors regulates pain transmission, neuroinflammation, and stress response.
21. Melanocortin Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of melanocortins to these receptors regulates energy balance, feeding behavior, and sexual function.
22. Endorphin Receptors (Mu, Delta, Kappa Opioid Receptors): These receptors are located in various brain regions and peripheral tissues. The binding of endorphins to these receptors modulates pain transmission, reward processing, and stress response.
23. Galanin Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of galanin to these receptors regulates feeding behavior, anxiety, and nociception.
24. Somatostatin Receptors: These receptors are located in various brain regions and peripheral tissues. The binding of somatostatin to these receptors modulates neurotransmitter release, hormone secretion, and cell proliferation.
25. Neuropeptide Y Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of neuropeptide Y to these receptors regulates feeding behavior, anxiety, and cardiovascular function.
26. Corticotropin-Releasing Hormone Receptors: These receptors are located in various brain regions and peripheral tissues. The binding of corticotropin-releasing hormone to these receptors modulates stress response, anxiety, and neuroinflammation.
27. Oxytocin Receptors: These receptors are found in various brain regions and peripheral tissues. The binding of oxytocin to these receptors regulates social behavior, maternal care, and anxiety.
28. Vasopressin Receptors: These receptors are located in various brain regions and peripheral tissues. The binding of vasopressin to these receptors modulates water balance, blood pressure, and social behavior.
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Hypothalamic diseases refer to conditions that affect the hypothalamus, a small but crucial region of the brain responsible for regulating many vital functions in the body. The hypothalamus helps control:

1. Body temperature
2. Hunger and thirst
3. Sleep cycles
4. Emotions and behavior
5. Release of hormones from the pituitary gland

Hypothalamic diseases can be caused by genetic factors, infections, tumors, trauma, or other conditions that damage the hypothalamus. Some examples of hypothalamic diseases include:

1. Hypothalamic dysfunction syndrome: A condition characterized by various symptoms such as obesity, sleep disturbances, and hormonal imbalances due to hypothalamic damage.
2. Kallmann syndrome: A genetic disorder that affects the development of the hypothalamus and results in a lack of sexual maturation and a decreased sense of smell.
3. Prader-Willi syndrome: A genetic disorder that causes obesity, developmental delays, and hormonal imbalances due to hypothalamic dysfunction.
4. Craniopharyngiomas: Tumors that develop near the pituitary gland and hypothalamus, often causing visual impairment, hormonal imbalances, and growth problems.
5. Infiltrative diseases: Conditions such as sarcoidosis or histiocytosis can infiltrate the hypothalamus, leading to various symptoms related to hormonal imbalances and neurological dysfunction.
6. Traumatic brain injury: Damage to the hypothalamus due to head trauma can result in various hormonal and neurological issues.
7. Infections: Bacterial or viral infections that affect the hypothalamus, such as encephalitis or meningitis, can cause damage and lead to hypothalamic dysfunction.

Treatment for hypothalamic diseases depends on the underlying cause and may involve medications, surgery, hormone replacement therapy, or other interventions to manage symptoms and improve quality of life.

Thyroid hormone receptors (THRs) are nuclear receptor proteins that bind to thyroid hormones, triiodothyronine (T3) and thyroxine (T4), and regulate gene transcription in target cells. These receptors play a crucial role in the development, growth, and metabolism of an organism by mediating the actions of thyroid hormones. THRs are encoded by genes THRA and THRB, which give rise to two major isoforms: TRα1 and TRβ1. Additionally, alternative splicing results in other isoforms with distinct tissue distributions and functions. THRs function as heterodimers with retinoid X receptors (RXRs) and bind to thyroid hormone response elements (TREs) in the regulatory regions of target genes. The binding of T3 or T4 to THRs triggers a conformational change, which leads to recruitment of coactivators or corepressors, ultimately resulting in activation or repression of gene transcription.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

A Growth Hormone-Secreting Pituitary Adenoma (GH-secreting pituitary adenoma, or GHoma) is a type of benign tumor that develops in the pituitary gland and results in excessive production of growth hormone (GH). This leads to a condition known as acromegaly if it occurs in adults, or gigantism if it occurs in children before the closure of the growth plates.

Symptoms of GH-secreting pituitary adenoma may include:

1. Coarsening of facial features
2. Enlargement of hands and feet
3. Deepened voice due to thickening of vocal cords
4. Increased sweating and body odor
5. Joint pain and stiffness
6. Sleep apnea
7. Fatigue, weakness, or muscle wasting
8. Headaches
9. Vision problems
10. Irregular menstrual periods in women
11. Erectile dysfunction in men

Diagnosis typically involves measuring the levels of GH and insulin-like growth factor 1 (IGF-1) in the blood, along with imaging tests like MRI or CT scans to locate and characterize the tumor. Treatment options include surgical removal of the tumor, radiation therapy, and medication to control GH production. Regular follow-ups are necessary to monitor for potential recurrence.

In medical terms, "ether" is an outdated term that was used to refer to a group of compounds known as diethyl ethers. The most common member of this group, and the one most frequently referred to as "ether," is diethyl ether, also known as sulfuric ether or simply ether.

Diethyl ether is a highly volatile, flammable liquid that was once widely used as an anesthetic agent in surgical procedures. It has a characteristic odor and produces a state of unconsciousness when inhaled, allowing patients to undergo surgery without experiencing pain. However, due to its numerous side effects, such as nausea, vomiting, and respiratory depression, as well as the risk of explosion or fire during use, it has largely been replaced by safer and more effective anesthetic agents.

It's worth noting that "ether" also has other meanings in different contexts, including a term used to describe a substance that produces a feeling of detachment from reality or a sense of unreality, as well as a class of organic compounds characterized by the presence of an ether group (-O-, a functional group consisting of an oxygen atom bonded to two alkyl or aryl groups).

Progesterone is a steroid hormone that is primarily produced in the ovaries during the menstrual cycle and in pregnancy. It plays an essential role in preparing the uterus for implantation of a fertilized egg and maintaining the early stages of pregnancy. Progesterone works to thicken the lining of the uterus, creating a nurturing environment for the developing embryo.

During the menstrual cycle, progesterone is produced by the corpus luteum, a temporary structure formed in the ovary after an egg has been released from a follicle during ovulation. If pregnancy does not occur, the levels of progesterone will decrease, leading to the shedding of the uterine lining and menstruation.

In addition to its reproductive functions, progesterone also has various other effects on the body, such as helping to regulate the immune system, supporting bone health, and potentially influencing mood and cognition. Progesterone can be administered medically in the form of oral pills, intramuscular injections, or vaginal suppositories for various purposes, including hormone replacement therapy, contraception, and managing certain gynecological conditions.

Pituitary ACTH hypersecretion, also known as Cushing's disease, is a condition characterized by the excessive production of adrenocorticotropic hormone (ACTH) from the pituitary gland. This results in an overproduction of cortisol, a steroid hormone produced by the adrenal glands, leading to a constellation of symptoms known as Cushing's syndrome.

In Cushing's disease, a benign tumor called an adenoma develops on the pituitary gland, causing it to release excess ACTH. This in turn stimulates the adrenal glands to produce more cortisol than necessary. The resulting high levels of cortisol can cause various symptoms such as weight gain, particularly around the trunk and face (central obesity), thinning of the skin, bruising, weakness, fatigue, mood changes, high blood pressure, and an increased risk of infections.

It is important to distinguish Cushing's disease from other causes of Cushing's syndrome, such as cortisol-producing adrenal tumors or exogenous sources of corticosteroid use, as the treatment approach may differ. Treatment for Cushing's disease typically involves surgical removal of the pituitary tumor, with additional medical management and/or radiation therapy in some cases.

Prolactin receptors are proteins found on the surface of various cells throughout the body that bind to the hormone prolactin. Once prolactin binds to its receptor, it activates a series of intracellular signaling pathways that regulate diverse physiological functions, including lactation, growth and development, metabolism, immune function, and behavior.

Prolactin receptors belong to the class I cytokine receptor family and are expressed in many tissues, including the mammary gland, pituitary gland, liver, kidney, adipose tissue, brain, and immune cells. In the mammary gland, prolactin signaling through its receptor is essential for milk production and breast development during pregnancy and lactation.

Abnormalities in prolactin receptor function have been implicated in several diseases, including cancer, infertility, and metabolic disorders. Therefore, understanding the structure, regulation, and function of prolactin receptors is crucial for developing new therapies to treat these conditions.

An ACTH-secreting pituitary adenoma is a type of tumor that develops in the pituitary gland, a small gland located at the base of the brain. This type of tumor is also known as Cushing's disease.

ACTH stands for adrenocorticotropic hormone, which is a hormone produced and released by the pituitary gland. ACTH stimulates the adrenal glands (small glands located on top of the kidneys) to produce cortisol, a steroid hormone that helps regulate metabolism, helps the body respond to stress, and suppresses inflammation.

In an ACTH-secreting pituitary adenoma, the tumor cells produce and release excessive amounts of ACTH, leading to overproduction of cortisol by the adrenal glands. This can result in a constellation of symptoms known as Cushing's syndrome, which may include weight gain (especially around the trunk), fatigue, muscle weakness, mood changes, thinning of the skin, easy bruising, and increased susceptibility to infections.

Treatment for an ACTH-secreting pituitary adenoma typically involves surgical removal of the tumor, followed by medications to manage cortisol levels if necessary. Radiation therapy may also be used in some cases.

Diagnostic techniques in endocrinology are methods used to identify and diagnose various endocrine disorders. These techniques include:

1. Hormone measurements: Measuring the levels of hormones in blood, urine, or saliva can help identify excess or deficiency of specific hormones. This is often done through immunoassays, which use antibodies to detect and quantify hormones.

2. Provocative and suppression tests: These tests involve administering a medication that stimulates or suppresses the release of a particular hormone. Blood samples are taken before and after the medication is given to assess changes in hormone levels. Examples include the glucose tolerance test for diabetes, the ACTH stimulation test for adrenal insufficiency, and the thyroid suppression test for hyperthyroidism.

3. Imaging studies: Various imaging techniques can be used to visualize endocrine glands and identify structural abnormalities such as tumors or nodules. These include X-rays, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine scans using radioactive tracers.

4. Genetic testing: Molecular genetic tests can be used to identify genetic mutations associated with certain endocrine disorders, such as multiple endocrine neoplasia type 1 or 2, or congenital adrenal hyperplasia.

5. Biopsy: In some cases, a small sample of tissue may be removed from an endocrine gland for microscopic examination (biopsy). This can help confirm the presence of cancer or other abnormalities.

6. Functional tests: These tests assess the ability of an endocrine gland to produce and secrete hormones in response to various stimuli. Examples include the glucagon stimulation test for gastrinoma and the calcium infusion test for hyperparathyroidism.

7. Wearable monitoring devices: Continuous glucose monitoring systems (CGMS) are wearable devices that measure interstitial glucose levels continuously over several days, providing valuable information about glycemic control in patients with diabetes.

Dwarfism is a medical condition that is characterized by short stature, typically with an adult height of 4 feet 10 inches (147 centimeters) or less. It is caused by a variety of genetic and medical conditions that affect bone growth, including skeletal dysplasias, hormonal deficiencies, and chromosomal abnormalities.

Skeletal dysplasias are the most common cause of dwarfism and are characterized by abnormalities in the development and growth of bones and cartilage. Achondroplasia is the most common form of skeletal dysplasia, accounting for about 70% of all cases of dwarfism. It is caused by a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene and results in short limbs, a large head, and a prominent forehead.

Hormonal deficiencies, such as growth hormone deficiency or hypothyroidism, can also cause dwarfism if they are not diagnosed and treated early. Chromosomal abnormalities, such as Turner syndrome (monosomy X) or Down syndrome (trisomy 21), can also result in short stature and other features of dwarfism.

It is important to note that people with dwarfism are not "dwarves" - the term "dwarf" is a medical and sociological term used to describe individuals with this condition, while "dwarves" is a term often used in fantasy literature and media to refer to mythical beings. The use of the term "dwarf" can be considered disrespectful or offensive to some people with dwarfism, so it is important to use respectful language when referring to individuals with this condition.

Somatostatin is a hormone that inhibits the release of several hormones and also has a role in slowing down digestion. It is produced by the body in various parts of the body, including the hypothalamus (a part of the brain), the pancreas, and the gastrointestinal tract.

Somatostatin exists in two forms: somatostatin-14 and somatostatin-28, which differ in their length. Somatostatin-14 is the predominant form found in the brain, while somatostatin-28 is the major form found in the gastrointestinal tract.

Somatostatin has a wide range of effects on various physiological processes, including:

* Inhibiting the release of several hormones such as growth hormone, insulin, glucagon, and gastrin
* Slowing down digestion by inhibiting the release of digestive enzymes from the pancreas and reducing blood flow to the gastrointestinal tract
* Regulating neurotransmission in the brain

Somatostatin is used clinically as a diagnostic tool for detecting certain types of tumors that overproduce growth hormone or other hormones, and it is also used as a treatment for some conditions such as acromegaly (a condition characterized by excessive growth hormone production) and gastrointestinal disorders.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

An ovary is a part of the female reproductive system in which ova or eggs are produced through the process of oogenesis. They are a pair of solid, almond-shaped structures located one on each side of the uterus within the pelvic cavity. Each ovary measures about 3 to 5 centimeters in length and weighs around 14 grams.

The ovaries have two main functions: endocrine (hormonal) function and reproductive function. They produce and release eggs (ovulation) responsible for potential fertilization and development of an embryo/fetus during pregnancy. Additionally, they are essential in the production of female sex hormones, primarily estrogen and progesterone, which regulate menstrual cycles, sexual development, and reproduction.

During each menstrual cycle, a mature egg is released from one of the ovaries into the fallopian tube, where it may be fertilized by sperm. If not fertilized, the egg, along with the uterine lining, will be shed, leading to menstruation.

Triiodothyronine (T3) is a thyroid hormone, specifically the active form of thyroid hormone, that plays a critical role in the regulation of metabolism, growth, and development in the human body. It is produced by the thyroid gland through the iodination and coupling of the amino acid tyrosine with three atoms of iodine. T3 is more potent than its precursor, thyroxine (T4), which has four iodine atoms, as T3 binds more strongly to thyroid hormone receptors and accelerates metabolic processes at the cellular level.

In circulation, about 80% of T3 is bound to plasma proteins, while the remaining 20% is unbound or free, allowing it to enter cells and exert its biological effects. The primary functions of T3 include increasing the rate of metabolic reactions, promoting protein synthesis, enhancing sensitivity to catecholamines (e.g., adrenaline), and supporting normal brain development during fetal growth and early infancy. Imbalances in T3 levels can lead to various medical conditions, such as hypothyroidism or hyperthyroidism, which may require clinical intervention and management.

Ovariectomy is a surgical procedure in which one or both ovaries are removed. It is also known as "ovary removal" or "oophorectomy." This procedure is often performed as a treatment for various medical conditions, including ovarian cancer, endometriosis, uterine fibroids, and pelvic pain. Ovariectomy can also be part of a larger surgical procedure called an hysterectomy, in which the uterus is also removed.

In some cases, an ovariectomy may be performed as a preventative measure for individuals at high risk of developing ovarian cancer. This is known as a prophylactic ovariectomy. After an ovariectomy, a person will no longer have menstrual periods and will be unable to become pregnant naturally. Hormone replacement therapy may be recommended in some cases to help manage symptoms associated with the loss of hormones produced by the ovaries.

Chromogranins are a group of proteins that are stored in the secretory vesicles of neuroendocrine cells, including neurons and endocrine cells. These proteins are co-released with neurotransmitters and hormones upon stimulation of the cells. Chromogranin A is the most abundant and best studied member of this protein family.

Chromogranins have several functions in the body. They play a role in the biogenesis, processing, and storage of neuropeptides and neurotransmitters within secretory vesicles. Additionally, chromogranins can be cleaved into smaller peptides, some of which have hormonal or regulatory activities. For example, vasostatin-1, a peptide derived from chromogranin A, has been shown to have vasodilatory and cardioprotective effects.

Measurement of chromogranin levels in blood can be used as a biomarker for the diagnosis and monitoring of neuroendocrine tumors, which are characterized by excessive secretion of chromogranins and other neuroendocrine markers.

Sexual maturation is the process of physical development during puberty that leads to the ability to reproduce. This process involves the development of primary and secondary sexual characteristics, changes in hormone levels, and the acquisition of reproductive capabilities. In females, this includes the onset of menstruation and the development of breasts and hips. In males, this includes the deepening of the voice, growth of facial hair, and the production of sperm. Achieving sexual maturation is an important milestone in human development and typically occurs during adolescence.

LHRH (Luteinizing Hormone-Releasing Hormone) receptors are a type of G protein-coupled receptor found on the surface of certain cells in the body, most notably in the anterior pituitary gland. These receptors bind to LHRH, a hormone that is produced and released by the hypothalamus in the brain.

When LHRH binds to its receptor, it triggers a series of intracellular signaling events that ultimately lead to the release of two other hormones from the anterior pituitary gland: luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones play critical roles in regulating reproductive function, including the development and maturation of sex cells (sperm and eggs), the production of sex steroid hormones (such as testosterone and estrogen), and the regulation of the menstrual cycle in females.

Disorders of the LHRH receptor or its signaling pathway can lead to a variety of reproductive disorders, including precocious puberty, delayed puberty, and infertility.

Insulin-like growth factor I (IGF-I) is a hormone that plays a crucial role in growth and development. It is a small protein with structural and functional similarity to insulin, hence the name "insulin-like." IGF-I is primarily produced in the liver under the regulation of growth hormone (GH).

IGF-I binds to its specific receptor, the IGF-1 receptor, which is widely expressed throughout the body. This binding activates a signaling cascade that promotes cell proliferation, differentiation, and survival. In addition, IGF-I has anabolic effects on various tissues, including muscle, bone, and cartilage, contributing to their growth and maintenance.

IGF-I is essential for normal growth during childhood and adolescence, and it continues to play a role in maintaining tissue homeostasis throughout adulthood. Abnormal levels of IGF-I have been associated with various medical conditions, such as growth disorders, diabetes, and certain types of cancer.

Neuropeptides are small protein-like molecules that are used by neurons to communicate with each other and with other cells in the body. They are produced in the cell body of a neuron, processed from larger precursor proteins, and then transported to the nerve terminal where they are stored in secretory vesicles. When the neuron is stimulated, the vesicles fuse with the cell membrane and release their contents into the extracellular space.

Neuropeptides can act as neurotransmitters or neuromodulators, depending on their target receptors and the duration of their effects. They play important roles in a variety of physiological processes, including pain perception, appetite regulation, stress response, and social behavior. Some neuropeptides also have hormonal functions, such as oxytocin and vasopressin, which are produced in the hypothalamus and released into the bloodstream to regulate reproductive and cardiovascular function, respectively.

There are hundreds of different neuropeptides that have been identified in the nervous system, and many of them have multiple functions and interact with other signaling molecules to modulate neural activity. Dysregulation of neuropeptide systems has been implicated in various neurological and psychiatric disorders, such as chronic pain, addiction, depression, and anxiety.

Gonadotropins are hormones that stimulate the gonads (sex glands) to produce sex steroids and gametes (sex cells). In humans, there are two main types of gonadotropins: follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which are produced and released by the anterior pituitary gland.

FSH plays a crucial role in the development and maturation of ovarian follicles in females and sperm production in males. LH triggers ovulation in females, causing the release of a mature egg from the ovary, and stimulates testosterone production in males.

Gonadotropins are often used in medical treatments to stimulate the gonads, such as in infertility therapies where FSH and LH are administered to induce ovulation or increase sperm production.

Neurosecretory systems are specialized components of the nervous system that produce and release chemical messengers called neurohormones. These neurohormones are released into the bloodstream and can have endocrine effects on various target organs in the body. The cells that make up neurosecretory systems, known as neurosecretory cells, are found in specific regions of the brain, such as the hypothalamus, and in peripheral nerves.

Neurosecretory systems play a critical role in regulating many physiological processes, including fluid and electrolyte balance, stress responses, growth and development, reproductive functions, and behavior. The neurohormones released by these systems can act synergistically or antagonistically to maintain homeostasis and coordinate the body's response to internal and external stimuli.

Neurosecretory cells are characterized by their ability to synthesize and store neurohormones in secretory granules, which are released upon stimulation. The release of neurohormones can be triggered by a variety of signals, including neural impulses, hormonal changes, and other physiological cues. Once released into the bloodstream, neurohormones can travel to distant target organs, where they bind to specific receptors and elicit a range of responses.

Overall, neurosecretory systems are an essential component of the neuroendocrine system, which plays a critical role in regulating many aspects of human physiology and behavior.

Estrogens are a group of steroid hormones that are primarily responsible for the development and regulation of female sexual characteristics and reproductive functions. They are also present in lower levels in males. The main estrogen hormone is estradiol, which plays a key role in promoting the growth and development of the female reproductive system, including the uterus, fallopian tubes, and breasts. Estrogens also help regulate the menstrual cycle, maintain bone density, and have important effects on the cardiovascular system, skin, hair, and cognitive function.

Estrogens are produced primarily by the ovaries in women, but they can also be produced in smaller amounts by the adrenal glands and fat cells. In men, estrogens are produced from the conversion of testosterone, the primary male sex hormone, through a process called aromatization.

Estrogen levels vary throughout a woman's life, with higher levels during reproductive years and lower levels after menopause. Estrogen therapy is sometimes used to treat symptoms of menopause, such as hot flashes and vaginal dryness, or to prevent osteoporosis in postmenopausal women. However, estrogen therapy also carries risks, including an increased risk of certain cancers, blood clots, and stroke, so it is typically recommended only for women who have a high risk of these conditions.

Homeodomain proteins are a group of transcription factors that play crucial roles in the development and differentiation of cells in animals and plants. They are characterized by the presence of a highly conserved DNA-binding domain called the homeodomain, which is typically about 60 amino acids long. The homeodomain consists of three helices, with the third helix responsible for recognizing and binding to specific DNA sequences.

Homeodomain proteins are involved in regulating gene expression during embryonic development, tissue maintenance, and organismal growth. They can act as activators or repressors of transcription, depending on the context and the presence of cofactors. Mutations in homeodomain proteins have been associated with various human diseases, including cancer, congenital abnormalities, and neurological disorders.

Some examples of homeodomain proteins include PAX6, which is essential for eye development, HOX genes, which are involved in body patterning, and NANOG, which plays a role in maintaining pluripotency in stem cells.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

The thyroid gland is a major endocrine gland located in the neck, anterior to the trachea and extends from the lower third of the Adams apple to the suprasternal notch. It has two lateral lobes, connected by an isthmus, and sometimes a pyramidal lobe. This gland plays a crucial role in the metabolism, growth, and development of the human body through the production of thyroid hormones (triiodothyronine/T3 and thyroxine/T4) and calcitonin. The thyroid hormones regulate body temperature, heart rate, and the production of protein, while calcitonin helps in controlling calcium levels in the blood. The function of the thyroid gland is controlled by the hypothalamus and pituitary gland through the thyroid-stimulating hormone (TSH).

I apologize, but "sheep" is not a term that has a medical definition. It is a common animal with the scientific name Ovis aries. If you have any medical or health-related questions, I would be happy to try and help answer those for you.

Growth disorders are medical conditions that affect a person's growth and development, leading to shorter or taller stature than expected for their age, sex, and ethnic group. These disorders can be caused by various factors, including genetic abnormalities, hormonal imbalances, chronic illnesses, malnutrition, and psychosocial issues.

There are two main types of growth disorders:

1. Short stature: This refers to a height that is significantly below average for a person's age, sex, and ethnic group. Short stature can be caused by various factors, including genetic conditions such as Turner syndrome or dwarfism, hormonal deficiencies, chronic illnesses, malnutrition, and psychosocial issues.
2. Tall stature: This refers to a height that is significantly above average for a person's age, sex, and ethnic group. Tall stature can be caused by various factors, including genetic conditions such as Marfan syndrome or Klinefelter syndrome, hormonal imbalances, and certain medical conditions like acromegaly.

Growth disorders can have significant impacts on a person's physical, emotional, and social well-being. Therefore, it is essential to diagnose and manage these conditions early to optimize growth and development and improve overall quality of life. Treatment options for growth disorders may include medication, nutrition therapy, surgery, or a combination of these approaches.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Corticosterone is a hormone produced by the adrenal gland in many animals, including humans. It is a type of glucocorticoid steroid hormone that plays an important role in the body's response to stress, immune function, metabolism, and regulation of inflammation. Corticosterone helps to regulate the balance of sodium and potassium in the body and also plays a role in the development and functioning of the nervous system. It is the primary glucocorticoid hormone in rodents, while cortisol is the primary glucocorticoid hormone in humans and other primates.

Pituitary hormone-regulating hormone receptors refer to specific protein structures found on the surface of certain cells in the body. These receptors are responsible for detecting and responding to hormones produced by the hypothalamus, which regulate the function of the pituitary gland.

The pituitary gland is a small gland located at the base of the brain that plays a critical role in regulating various bodily functions, including growth and development, metabolism, reproduction, and stress response. The hypothalamus produces hormones that either stimulate or inhibit the release of pituitary hormones, which then act on target organs throughout the body to regulate their function.

Pituitary hormone-regulating hormone receptors are found on the surface of pituitary cells and are specific to individual hypothalamic hormones. When a hypothalamic hormone binds to its corresponding receptor, it triggers a series of intracellular signals that ultimately result in the release or inhibition of pituitary hormones.

Examples of pituitary hormone-regulating hormone receptors include:

* Thyroid-stimulating hormone (TSH) receptor, which responds to thyrotropin-releasing hormone (TRH) from the hypothalamus.
* Adrenocorticotropic hormone (ACTH) receptor, which responds to corticotropin-releasing hormone (CRH) from the hypothalamus.
* Growth hormone-releasing hormone (GHRH) receptor, which responds to GHRH from the hypothalamus.
* Gonadotropin-releasing hormone (GnRH) receptor, which responds to GnRH from the hypothalamus.
* Prolactin-inhibiting hormone (PIH) receptor, which responds to dopamine from the hypothalamus.

Abnormalities in pituitary hormone-regulating hormone receptors can lead to various endocrine disorders, such as hypothyroidism, Cushing's disease, acromegaly, and infertility.

Gonadotrophs are a type of hormone-secreting cells located in the anterior pituitary gland, a small endocrine gland at the base of the brain. These cells produce and release two important gonadotropin hormones: follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Follicle-stimulating hormone (FSH) plays a crucial role in the reproductive system by stimulating the growth and development of ovarian follicles in females and sperm production in males. In females, FSH also promotes the production of estrogen during the menstrual cycle.

Luteinizing hormone (LH) is responsible for triggering ovulation in females, releasing a mature egg from the ovary into the fallopian tube. In addition, LH stimulates the production of progesterone by the remaining cells of the ruptured follicle, which forms the corpus luteum. In males, LH helps regulate testosterone production in the testes.

Gonadotrophs are essential for maintaining reproductive function and hormonal balance in both sexes. Their activity is controlled by the hypothalamus, another part of the brain that releases gonadotropin-releasing hormone (GnRH) to regulate FSH and LH secretion.

Chorionic Gonadotropin (hCG) is a hormone that is produced during pregnancy. It is produced by the placenta after implantation of the fertilized egg in the uterus. The main function of hCG is to prevent the disintegration of the corpus luteum, which is a temporary endocrine structure that forms in the ovary after ovulation and produces progesterone during early pregnancy. Progesterone is essential for maintaining the lining of the uterus and supporting the pregnancy.

hCG can be detected in the blood or urine as early as 10 days after conception, and its levels continue to rise throughout the first trimester of pregnancy. In addition to its role in maintaining pregnancy, hCG is also used as a clinical marker for pregnancy and to monitor certain medical conditions such as gestational trophoblastic diseases.

Luteinizing Hormone (LH) is a glycoprotein hormone secreted by the anterior pituitary gland. It plays a crucial role in regulating the reproductive system. The beta subunit of LH is one of the two non-identical polypeptide chains that make up the LH molecule (the other being the alpha subunit, which is common to several hormones).

The beta subunit of LH is unique to LH and is often used in assays to measure and determine the concentration of LH in blood or urine. It's responsible for the biological specificity and activity of the LH hormone. Any changes in the structure of this subunit can affect the function of LH, which in turn can have implications for reproductive processes such as ovulation and testosterone production.

Pregnancy is a physiological state or condition where a fertilized egg (zygote) successfully implants and grows in the uterus of a woman, leading to the development of an embryo and finally a fetus. This process typically spans approximately 40 weeks, divided into three trimesters, and culminates in childbirth. Throughout this period, numerous hormonal and physical changes occur to support the growing offspring, including uterine enlargement, breast development, and various maternal adaptations to ensure the fetus's optimal growth and well-being.

Acromegaly is a rare hormonal disorder that typically occurs in middle-aged adults. It results from the pituitary gland producing too much growth hormone (GH) during adulthood. The excessive production of GH leads to abnormal growth of body tissues, particularly in the hands, feet, and face.

The term "acromegaly" is derived from two Greek words: "akros," meaning extremities, and "megaly," meaning enlargement. In most cases, acromegaly is caused by a benign tumor (adenoma) of the pituitary gland, which results in overproduction of GH.

Common symptoms include enlarged hands and feet, coarse facial features, deepened voice, joint pain, and sweating. If left untreated, acromegaly can lead to serious complications such as diabetes, hypertension, heart disease, and arthritis. Treatment usually involves surgical removal of the tumor, radiation therapy, or medication to control GH production.

A chromophobe adenoma is a type of benign (non-cancerous) tumor that typically arises in the pituitary gland, which is a small endocrine gland located at the base of the brain. The term "chromophobe" refers to the appearance of the cells under a microscope - they lack pigment and have a characteristic appearance with abundant clear or lightly stained cytoplasm.

Chromophobe adenomas are slow-growing tumors that can vary in size, and they may cause symptoms due to pressure on surrounding structures or by producing excess hormones. The most common hormone produced by chromophobe adenomas is prolactin, leading to symptoms such as menstrual irregularities, milk production (galactorrhea), and decreased sexual function in women, and decreased libido, erectile dysfunction, and infertility in men.

Treatment for chromophobe adenomas typically involves surgical removal of the tumor, often through a transsphenoidal approach (through the nose and sphenoid sinus). In some cases, radiation therapy or medical management with hormone-blocking drugs may also be necessary. Regular follow-up with an endocrinologist is important to monitor for any recurrence or hormonal imbalances.

Somatotrophs are a type of cell found within the anterior pituitary gland, a small endocrine gland located at the base of the brain. These cells are responsible for producing and secreting the hormone known as somatotropin or growth hormone (GH). This hormone plays a crucial role in regulating growth, cell reproduction, and regeneration. It also helps to regulate the body's metabolism and maintain proper body composition by promoting the breakdown of fats and the synthesis of proteins. Disorders related to somatotrophs can lead to conditions such as gigantism or dwarfism, depending on whether there is an overproduction or underproduction of growth hormone.

"Fish proteins" are not a recognized medical term or concept. However, fish is a source of protein that is often consumed in the human diet and has been studied in various medical and nutritional contexts. According to the USDA FoodData Central database, a 100-gram serving of cooked Atlantic salmon contains approximately 25 grams of protein.

Proteins from fish, like other animal proteins, are complete proteins, meaning they contain all nine essential amino acids that cannot be synthesized by the human body and must be obtained through the diet. Fish proteins have been studied for their potential health benefits, including their role in muscle growth and repair, immune function, and cardiovascular health.

It's worth noting that some people may have allergies to fish or seafood, which can cause a range of symptoms from mild skin irritation to severe anaphylaxis. If you suspect you have a fish allergy, it's important to consult with a healthcare professional for proper diagnosis and management.

Pituitary adenylate cyclase-activating polypeptide (PACAP) receptors are a type of G protein-coupled receptor that bind and respond to PACAP, a neuropeptide involved in various physiological functions such as neurotransmission, vasodilation, and hormone release. There are two main types of PACAP receptors: PAC1 and VPAC1/VPAC2. These receptors play important roles in the regulation of various bodily processes, including the stress response, circadian rhythms, and energy metabolism. Upon activation by PACAP, these receptors trigger a signaling cascade that leads to the activation of adenylate cyclase and an increase in intracellular cAMP levels, which in turn regulates various cellular responses.

Hypothalamic hormones are a group of hormones that are produced and released by the hypothalamus, a small region at the base of the brain. These hormones play a crucial role in regulating various bodily functions, including temperature, hunger, thirst, sleep, and emotional behavior.

The hypothalamus produces two main types of hormones: releasing hormones and inhibiting hormones. Releasing hormones stimulate the pituitary gland to release its own hormones, while inhibiting hormones prevent the pituitary gland from releasing hormones.

Some examples of hypothalamic hormones include:

* Thyroid-releasing hormone (TRH), which stimulates the release of thyroid-stimulating hormone (TSH) from the pituitary gland.
* Growth hormone-releasing hormone (GHRH) and somatostatin, which regulate the release of growth hormone (GH) from the pituitary gland.
* Gonadotropin-releasing hormone (GnRH), which stimulates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland, which in turn regulate reproductive function.
* Corticotropin-releasing hormone (CRH), which stimulates the release of adrenocorticotropic hormone (ACTH) from the pituitary gland, which regulates the stress response.
* Prolactin-inhibiting hormone (PIH) and prolactin-releasing hormone (PRH), which regulate the release of prolactin from the pituitary gland, which is involved in lactation.

Overall, hypothalamic hormones play a critical role in maintaining homeostasis in the body by regulating various physiological processes.

Transcription factors are proteins that play a crucial role in regulating gene expression by controlling the transcription of DNA to messenger RNA (mRNA). They function by binding to specific DNA sequences, known as response elements, located in the promoter region or enhancer regions of target genes. This binding can either activate or repress the initiation of transcription, depending on the properties and interactions of the particular transcription factor. Transcription factors often act as part of a complex network of regulatory proteins that determine the precise spatiotemporal patterns of gene expression during development, differentiation, and homeostasis in an organism.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Melanocyte-stimulating hormones (MSH) are a group of peptide hormones that originate from the precursor protein proopiomelanocortin (POMC). They play crucial roles in various physiological processes, including pigmentation, energy balance, and appetite regulation.

There are several types of MSH, but the most well-known ones include α-MSH, β-MSH, and γ-MSH. These hormones bind to melanocortin receptors (MCRs), which are found in various tissues throughout the body. The binding of MSH to MCRs triggers a series of intracellular signaling events that ultimately lead to changes in cell behavior.

In the context of skin physiology, α-MSH and β-MSH bind to melanocortin 1 receptor (MC1R) on melanocytes, which are the cells responsible for producing pigment (melanin). This binding stimulates the production and release of eumelanin, a type of melanin that is brown or black in color. As a result, increased levels of MSH can lead to darkening of the skin, also known as hyperpigmentation.

Apart from their role in pigmentation, MSH hormones have been implicated in several other physiological processes. For instance, α-MSH has been shown to suppress appetite and promote weight loss by binding to melanocortin 4 receptor (MC4R) in the hypothalamus, a region of the brain that regulates energy balance. Additionally, MSH hormones have been implicated in inflammation, immune response, and sexual function.

Overall, melanocyte-stimulating hormones are a diverse group of peptide hormones that play important roles in various physiological processes, including pigmentation, energy balance, and appetite regulation.

Juvenile hormones (JHs) are a class of sesquiterpenoid compounds that play a crucial role in the regulation of insect development, reproduction, and other physiological processes. They are primarily produced by the corpora allata, a pair of endocrine glands located in the head of insects.

JHs are essential for maintaining the larval or nymphal stage of insects, preventing the expression of adult characteristics during molting. As the concentration of JH decreases in the hemolymph (insect blood), a molt to the next developmental stage occurs, and if the insect has reached its final instar, it will metamorphose into an adult.

In addition to their role in development, JHs also influence various aspects of insect reproductive physiology, such as vitellogenesis (yolk protein synthesis), oocyte maturation, and spermatogenesis. Furthermore, JHs have been implicated in regulating diapause (a period of suspended development during unfavorable environmental conditions) and caste determination in social insects like bees and ants.

Overall, juvenile hormones are vital regulators of growth, development, and reproduction in insects, making them attractive targets for the development of novel pest management strategies.

The adrenal glands are a pair of endocrine glands that are located on top of the kidneys. Each gland has two parts: the outer cortex and the inner medulla. The adrenal cortex produces hormones such as cortisol, aldosterone, and androgens, which regulate metabolism, blood pressure, and other vital functions. The adrenal medulla produces catecholamines, including epinephrine (adrenaline) and norepinephrine (noradrenaline), which help the body respond to stress by increasing heart rate, blood pressure, and alertness.

Pituitary irradiation is a medical procedure that involves the use of targeted radiation therapy to treat conditions affecting the pituitary gland, a small endocrine gland located at the base of the brain. The pituitary gland controls various hormonal functions in the body, and any abnormalities or tumors in this area can lead to hormonal imbalances and other related health issues.

In pituitary irradiation, a radiation oncologist uses external beam radiation therapy (EBRT) to deliver precise and focused doses of high-energy radiation to the pituitary gland. The goal is to destroy or shrink the tumor while minimizing damage to surrounding healthy tissues. This procedure can be used as a primary treatment option, an adjuvant therapy following surgery, or in cases where surgical intervention is not feasible or has been unsuccessful.

The effects of pituitary irradiation on hormone production may take months or even years to manifest fully. Patients will typically require regular follow-ups with their healthcare team to monitor hormonal levels and manage any potential side effects, which can include fatigue, headaches, vision changes, and cognitive impairment. In some cases, hormone replacement therapy might be necessary to address hormonal deficiencies resulting from the treatment.

Ovulation is the medical term for the release of a mature egg from an ovary during a woman's menstrual cycle. The released egg travels through the fallopian tube where it may be fertilized by sperm if sexual intercourse has occurred recently. If the egg is not fertilized, it will break down and leave the body along with the uterine lining during menstruation. Ovulation typically occurs around day 14 of a 28-day menstrual cycle, but the timing can vary widely from woman to woman and even from cycle to cycle in the same woman.

During ovulation, there are several physical changes that may occur in a woman's body, such as an increase in basal body temperature, changes in cervical mucus, and mild cramping or discomfort on one side of the lower abdomen (known as mittelschmerz). These symptoms can be used to help predict ovulation and improve the chances of conception.

It's worth noting that some medical conditions, such as polycystic ovary syndrome (PCOS) or premature ovarian failure, may affect ovulation and make it difficult for a woman to become pregnant. In these cases, medical intervention may be necessary to help promote ovulation and increase the chances of conception.

Peptide hormones are a type of hormone consisting of short chains of amino acids known as peptides. They are produced and released by various endocrine glands and play crucial roles in regulating many physiological processes in the body, including growth and development, metabolism, stress response, and reproductive functions.

Peptide hormones exert their effects by binding to specific receptors on the surface of target cells, which triggers a series of intracellular signaling events that ultimately lead to changes in cell behavior or function. Some examples of peptide hormones include insulin, glucagon, growth hormone, prolactin, oxytocin, and vasopressin.

Peptide hormones are synthesized as larger precursor proteins called prohormones, which are cleaved by enzymes to release the active peptide hormone. They are water-soluble and cannot pass through the cell membrane, so they exert their effects through autocrine, paracrine, or endocrine mechanisms. Autocrine signaling occurs when a cell releases a hormone that binds to receptors on the same cell, while paracrine signaling involves the release of a hormone that acts on nearby cells. Endocrine signaling, on the other hand, involves the release of a hormone into the bloodstream, which then travels to distant target cells to exert its effects.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

The testis, also known as the testicle, is a male reproductive organ that is part of the endocrine system. It is located in the scrotum, outside of the abdominal cavity. The main function of the testis is to produce sperm and testosterone, the primary male sex hormone.

The testis is composed of many tiny tubules called seminiferous tubules, where sperm are produced. These tubules are surrounded by a network of blood vessels, nerves, and supportive tissues. The sperm then travel through a series of ducts to the epididymis, where they mature and become capable of fertilization.

Testosterone is produced in the Leydig cells, which are located in the interstitial tissue between the seminiferous tubules. Testosterone plays a crucial role in the development and maintenance of male secondary sexual characteristics, such as facial hair, deep voice, and muscle mass. It also supports sperm production and sexual function.

Abnormalities in testicular function can lead to infertility, hormonal imbalances, and other health problems. Regular self-examinations and medical check-ups are recommended for early detection and treatment of any potential issues.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

The pituitary gland is divided into three lobes: the anterior lobe (adenohypophysis), the posterior lobe (neurohypophysis), and the intermediate lobe (intermedia). The medical definition of 'Pituitary Gland, Intermediate' refers to this small and less defined region located between the anterior and posterior pituitary lobes.

The intermediate lobe is primarily responsible for producing and secreting several important hormones, most notably pro-opiomelanocortin (POMC)-derived peptides such as melanocyte-stimulating hormone (MSH) and endorphins. These hormones play crucial roles in various physiological processes, including skin pigmentation, energy balance, and pain modulation.

However, it is important to note that the intermediate lobe's activity and hormonal secretion are minimal in humans compared to other mammals. In fact, some researchers question whether the human intermediate lobe even functions at all under normal conditions due to its rudimentary nature. Nevertheless, understanding the structure and function of the pituitary gland's intermediate lobe is essential for comparative endocrinology and may provide insights into the evolution of the pituitary gland across different species.

Gonadal hormones, also known as sex hormones, are steroid hormones that are primarily produced by the gonads (ovaries in females and testes in males). They play crucial roles in the development and regulation of sexual characteristics and reproductive functions. The three main types of gonadal hormones are:

1. Estrogens - predominantly produced by ovaries, they are essential for female sexual development and reproduction. The most common estrogen is estradiol, which supports the growth and maintenance of secondary sexual characteristics in women, such as breast development and wider hips. Estrogens also play a role in regulating the menstrual cycle and maintaining bone health.

2. Progesterone - primarily produced by ovaries during the menstrual cycle and pregnancy, progesterone prepares the uterus for implantation of a fertilized egg and supports the growth and development of the fetus during pregnancy. It also plays a role in regulating the menstrual cycle.

3. Androgens - produced by both ovaries and testes, but primarily by testes in males. The most common androgen is testosterone, which is essential for male sexual development and reproduction. Testosterone supports the growth and maintenance of secondary sexual characteristics in men, such as facial hair, a deeper voice, and increased muscle mass. It also plays a role in regulating sex drive (libido) and bone health in both males and females.

In summary, gonadal hormones are steroid hormones produced by the gonads that play essential roles in sexual development, reproduction, and maintaining secondary sexual characteristics.

Pituitary adenylate cyclase-activating polypeptide type I receptor (PAC1-R) is a type of G protein-coupled receptor that binds to and is activated by the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP). PAC1-R is widely expressed in various tissues, including the central nervous system, endocrine organs, and the cardiovascular system. Activation of PAC1-R leads to the activation of adenylate cyclase and an increase in intracellular cAMP levels, which in turn activates downstream signaling pathways involved in a variety of physiological processes such as neurotransmission, hormone secretion, and vasodilation. Abnormalities in PAC1-R function have been implicated in several diseases, including migraine, depression, and certain types of cancer.

Hormone antagonists are substances or drugs that block the action of hormones by binding to their receptors without activating them, thereby preventing the hormones from exerting their effects. They can be classified into two types: receptor antagonists and enzyme inhibitors. Receptor antagonists bind directly to hormone receptors and prevent the hormone from binding, while enzyme inhibitors block the production or breakdown of hormones by inhibiting specific enzymes involved in their metabolism. Hormone antagonists are used in the treatment of various medical conditions, such as cancer, hormonal disorders, and cardiovascular diseases.

Dexamethasone is a type of corticosteroid medication, which is a synthetic version of a natural hormone produced by the adrenal glands. It is often used to reduce inflammation and suppress the immune system in a variety of medical conditions, including allergies, asthma, rheumatoid arthritis, and certain skin conditions.

Dexamethasone works by binding to specific receptors in cells, which triggers a range of anti-inflammatory effects. These include reducing the production of chemicals that cause inflammation, suppressing the activity of immune cells, and stabilizing cell membranes.

In addition to its anti-inflammatory effects, dexamethasone can also be used to treat other medical conditions, such as certain types of cancer, brain swelling, and adrenal insufficiency. It is available in a variety of forms, including tablets, liquids, creams, and injectable solutions.

Like all medications, dexamethasone can have side effects, particularly if used for long periods of time or at high doses. These may include mood changes, increased appetite, weight gain, acne, thinning skin, easy bruising, and an increased risk of infections. It is important to follow the instructions of a healthcare provider when taking dexamethasone to minimize the risk of side effects.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Thyroid hormone receptors (THRs) are nuclear receptor proteins that bind to thyroid hormones and mediate their effects in target cells. There are two main types of THRs, referred to as THR alpha and THR beta. THR beta is further divided into two subtypes, THR beta1 and THR beta2.

THR beta is a type of nuclear receptor that is primarily expressed in the liver, kidney, and heart, as well as in the central nervous system. It plays an important role in regulating the metabolism of carbohydrates, lipids, and proteins, as well as in the development and function of the heart. THR beta is also involved in the regulation of body weight and energy expenditure.

THR beta1 is the predominant subtype expressed in the liver and is responsible for many of the metabolic effects of thyroid hormones in this organ. THR beta2, on the other hand, is primarily expressed in the heart and plays a role in regulating cardiac function.

Abnormalities in THR beta function can lead to various diseases, including thyroid hormone resistance, a condition in which the body's cells are unable to respond properly to thyroid hormones. This can result in symptoms such as weight gain, fatigue, and cold intolerance.

Thyrotropin-releasing hormone (TRH) receptors are a type of G protein-coupled receptor found in the pituitary gland and other tissues throughout the body. TRH is a tripeptide hormone that plays a crucial role in regulating the release of thyroid-stimulating hormone (TSH) from the anterior pituitary gland.

TRH receptors are activated when TRH binds to them, which triggers a signaling cascade that ultimately leads to an increase in intracellular calcium and the release of TSH. In addition to regulating TSH secretion, TRH receptors have been found to play a role in various physiological processes, including feeding behavior, energy metabolism, and neuroprotection.

Abnormalities in TRH receptor function have been implicated in several endocrine disorders, such as thyroid dysfunction and obesity. Therefore, understanding the structure and function of TRH receptors is essential for developing new therapeutic strategies to treat these conditions.

Insulin is a hormone produced by the beta cells of the pancreatic islets, primarily in response to elevated levels of glucose in the circulating blood. It plays a crucial role in regulating blood glucose levels and facilitating the uptake and utilization of glucose by peripheral tissues, such as muscle and adipose tissue, for energy production and storage. Insulin also inhibits glucose production in the liver and promotes the storage of excess glucose as glycogen or triglycerides.

Deficiency in insulin secretion or action leads to impaired glucose regulation and can result in conditions such as diabetes mellitus, characterized by chronic hyperglycemia and associated complications. Exogenous insulin is used as a replacement therapy in individuals with diabetes to help manage their blood glucose levels and prevent long-term complications.

In situ hybridization (ISH) is a molecular biology technique used to detect and localize specific nucleic acid sequences, such as DNA or RNA, within cells or tissues. This technique involves the use of a labeled probe that is complementary to the target nucleic acid sequence. The probe can be labeled with various types of markers, including radioisotopes, fluorescent dyes, or enzymes.

During the ISH procedure, the labeled probe is hybridized to the target nucleic acid sequence in situ, meaning that the hybridization occurs within the intact cells or tissues. After washing away unbound probe, the location of the labeled probe can be visualized using various methods depending on the type of label used.

In situ hybridization has a wide range of applications in both research and diagnostic settings, including the detection of gene expression patterns, identification of viral infections, and diagnosis of genetic disorders.

Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein or RNA molecule. This process involves several steps: transcription, RNA processing, and translation. During transcription, the genetic information in DNA is copied into a complementary RNA molecule, known as messenger RNA (mRNA). The mRNA then undergoes RNA processing, which includes adding a cap and tail to the mRNA and splicing out non-coding regions called introns. The resulting mature mRNA is then translated into a protein on ribosomes in the cytoplasm through the process of translation.

The regulation of gene expression is a complex and highly controlled process that allows cells to respond to changes in their environment, such as growth factors, hormones, and stress signals. This regulation can occur at various stages of gene expression, including transcriptional activation or repression, RNA processing, mRNA stability, and translation. Dysregulation of gene expression has been implicated in many diseases, including cancer, genetic disorders, and neurological conditions.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Anti-Mullerian Hormone (AMH) is a glycoprotein hormone that belongs to the transforming growth factor-beta (TGF-β) family. It is primarily produced by the granulosa cells of developing follicles in the ovaries of females. AMH plays an essential role in female reproductive physiology, as it inhibits the recruitment and further development of primordial follicles, thereby regulating the size of the primordial follicle pool and the onset of puberty.

AMH levels are often used as a biomarker for ovarian reserve assessment in women. High AMH levels indicate a larger ovarian reserve, while low levels suggest a decreased reserve, which may be associated with reduced fertility or an earlier onset of menopause. Additionally, measuring AMH levels can help predict the response to ovarian stimulation during assisted reproductive technologies (ART) such as in vitro fertilization (IVF).

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

"Body height" is a measure of the vertical length of a person's body from the top of their head to the bottom of their feet. It is typically measured in units such as centimeters (cm) or inches (in). In medical settings, body height is often used as a basic anthropometric measurement to assess overall health status, growth and development, nutritional status, and aging-related changes.

There are different methods for measuring body height, but the most common one involves having the person stand upright against a vertical surface (such as a wall or a stadiometer) with their heels, buttocks, shoulders, and head touching the surface. The measurement is taken at the point where the top of the person's head meets the surface.

Body height can be influenced by various factors, including genetics, nutrition, health status, and environmental conditions. Changes in body height over time can provide important insights into a person's health trajectory and potential health risks. For example, a significant decrease in body height may indicate bone loss or spinal compression, while a rapid increase in height during childhood or adolescence may suggest optimal growth and development.

Castration is a surgical procedure to remove the testicles in males or ovaries in females. In males, it is also known as orchiectomy. This procedure results in the inability to produce sex hormones and gametes (sperm in men and eggs in women), and can be done for various reasons such as medical treatment for certain types of cancer, to reduce sexual urges in individuals with criminal tendencies, or as a form of birth control in animals.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Corticotrophs are a type of endocrine cell found in the anterior pituitary gland. They are responsible for producing and secreting adrenocorticotropic hormone (ACTH), which regulates the function of the adrenal gland. ACTH stimulates the production and release of cortisol, a steroid hormone that helps regulate metabolism, immune response, and stress response among other functions. Corticotrophs are controlled by the hypothalamus through the release of corticotropin-releasing hormone (CRH) and vasopressin. Dysfunction of corticotrophs can lead to various endocrine disorders, such as Cushing's disease, which is characterized by excessive production of ACTH and cortisol.

Gastrointestinal (GI) hormones are a group of hormones that are secreted by cells in the gastrointestinal tract in response to food intake and digestion. They play crucial roles in regulating various physiological processes, including appetite regulation, gastric acid secretion, motility of the gastrointestinal tract, insulin secretion, and pancreatic enzyme release.

Examples of GI hormones include:

* Gastrin: Secreted by G cells in the stomach, gastrin stimulates the release of hydrochloric acid from parietal cells in the stomach lining.
* Ghrelin: Produced by the stomach, ghrelin is often referred to as the "hunger hormone" because it stimulates appetite and food intake.
* Cholecystokinin (CCK): Secreted by I cells in the small intestine, CCK promotes digestion by stimulating the release of pancreatic enzymes and bile from the liver. It also inhibits gastric emptying and reduces appetite.
* Gastric inhibitory peptide (GIP): Produced by K cells in the small intestine, GIP promotes insulin secretion and inhibits glucagon release.
* Secretin: Released by S cells in the small intestine, secretin stimulates the pancreas to produce bicarbonate-rich fluid that neutralizes stomach acid in the duodenum.
* Motilin: Secreted by MO cells in the small intestine, motilin promotes gastrointestinal motility and regulates the migrating motor complex (MMC), which is responsible for cleaning out the small intestine between meals.

These hormones work together to regulate digestion and maintain homeostasis in the body. Dysregulation of GI hormones can contribute to various gastrointestinal disorders, such as gastroparesis, irritable bowel syndrome (IBS), and diabetes.

Lactotrophs, also known as mammotrophs or prolactin cells, are a type of hormone-producing cell found in the anterior pituitary gland. They are responsible for producing and secreting the hormone prolactin, which plays a crucial role in lactation (milk production) in females after childbirth. Prolactin also has other functions in the body, such as regulating immune responses, metabolism, and behavior. Lactotrophs can be stimulated by factors like estrogen, thyroid-stimulating hormone (TSH), and stress, leading to increased prolactin secretion.

Bromocriptine is a dopamine receptor agonist drug, which means it works by binding to and activating dopamine receptors in the brain. It has several therapeutic uses, including:

* Treatment of Parkinson's disease: Bromocriptine can be used alone or in combination with levodopa to help manage the symptoms of Parkinson's disease, such as stiffness, tremors, spasms, and poor muscle control.
* Suppression of lactation: Bromocriptine can be used to suppress milk production in women who are not breastfeeding or who have stopped breastfeeding but still have high levels of prolactin, a hormone that stimulates milk production.
* Treatment of pituitary tumors: Bromocriptine can be used to shrink certain types of pituitary tumors, such as prolactinomas, which are tumors that secrete excessive amounts of prolactin.
* Management of acromegaly: Bromocriptine can be used to manage the symptoms of acromegaly, a rare hormonal disorder characterized by abnormal growth and enlargement of body tissues, by reducing the production of growth hormone.

Bromocriptine is available in immediate-release and long-acting formulations, and it is usually taken orally. Common side effects of bromocriptine include nausea, dizziness, lightheadedness, and drowsiness. Serious side effects are rare but can include hallucinations, confusion, and priapism (prolonged erection).

Somatotropin receptors are a type of cell surface receptor that binds to and gets activated by the hormone somatotropin, also known as growth hormone (GH). These receptors are found in many tissues throughout the body, including the liver, muscle, and fat. When somatotropin binds to its receptor, it activates a series of intracellular signaling pathways that regulate various physiological processes such as growth, metabolism, and cell reproduction.

Somatotropin receptors belong to the class I cytokine receptor family and are composed of two subunits, a homodimer of extracellular glycoproteins that bind to the hormone and an intracellular tyrosine kinase domain that activates downstream signaling pathways. Mutations in the somatotropin receptor gene can lead to growth disorders such as dwarfism or gigantism, depending on whether the mutation results in a decrease or increase in receptor activity.

Macrophage migration-inhibitory factors (MIFs) are a group of proteins that were initially identified for their ability to inhibit the random migration of macrophages. However, subsequent research has revealed that MIFs have diverse functions in the immune system and other biological processes. They play crucial roles in inflammation, immunoregulation, and stress responses.

MIF is constitutively expressed and secreted by various cell types, including T-cells, macrophages, epithelial cells, endothelial cells, and neurons. It functions as a proinflammatory cytokine that can counteract the anti-inflammatory effects of glucocorticoids. MIF is involved in several signaling pathways and contributes to various physiological and pathophysiological processes, such as cell growth, differentiation, and survival.

Dysregulation of MIF has been implicated in numerous diseases, including autoimmune disorders, cancer, cardiovascular diseases, and neurodegenerative conditions. Therefore, understanding the functions and regulation of MIFs is essential for developing novel therapeutic strategies to target these diseases.

Inhibins are a group of protein hormones that play a crucial role in regulating the function of the reproductive system, specifically by inhibiting the production of follicle-stimulating hormone (FSH) in the pituitary gland. They are produced and secreted primarily by the granulosa cells in the ovaries of females and Sertoli cells in the testes of males.

Inhibins consist of two subunits, an alpha subunit, and a beta subunit, which can be further divided into two types: inhibin A and inhibin B. Inhibin A is primarily produced by the granulosa cells of developing follicles in the ovary, while inhibin B is mainly produced by the Sertoli cells in the testes.

By regulating FSH production, inhibins help control the development and maturation of ovarian follicles in females and spermatogenesis in males. Abnormal levels of inhibins have been associated with various reproductive disorders, including polycystic ovary syndrome (PCOS) and certain types of cancer.

Cushing syndrome is a hormonal disorder that occurs when your body is exposed to high levels of the hormone cortisol for a long time. This can happen due to various reasons such as taking high doses of corticosteroid medications or tumors that produce cortisol or adrenocorticotropic hormone (ACTH).

The symptoms of Cushing syndrome may include:

* Obesity, particularly around the trunk and upper body
* Thinning of the skin, easy bruising, and purple or red stretch marks on the abdomen, thighs, breasts, and arms
* Weakened bones, leading to fractures
* High blood pressure
* High blood sugar
* Mental changes such as depression, anxiety, and irritability
* Increased fatigue and weakness
* Menstrual irregularities in women
* Decreased fertility in men

Cushing syndrome can be diagnosed through various tests, including urine and blood tests to measure cortisol levels, saliva tests, and imaging tests to locate any tumors. Treatment depends on the cause of the condition but may include surgery, radiation therapy, chemotherapy, or adjusting medication dosages.

Securin is not a medical term, but rather a biological concept related to cell division. It's a protein that plays a crucial role in the regulation of chromosome separation during cell division (mitosis).

During mitosis, sister chromatids (identical copies of a chromosome) are held together by cohesin proteins until it's time for them to separate and move to opposite ends of the cell. Securin is one of the proteins that helps regulate this process. Specifically, securin inhibits an enzyme called separase, which is responsible for cleaving the cohesin rings that hold sister chromatids together.

Once the cell is ready to separate its chromosomes, a protease called separase is activated and degrades securin. This allows separase to cleave the cohesin rings, leading to the separation of sister chromatids and the continuation of mitosis. If securin function is disrupted, it can lead to errors in chromosome segregation, which can contribute to genomic instability and diseases like cancer.

Thyrotrophs, also known as thyroid-stimulating hormone (TSH) producing cells, are a type of endocrine cell located in the anterior pituitary gland. They synthesize and secrete TSH, which is a hormone that regulates the function of the thyroid gland by stimulating the production and release of thyroxine (T4) and triiodothyronine (T3), two important thyroid hormones. Thyrotrophs respond to the levels of thyroid hormones in the blood through a negative feedback mechanism, increasing or decreasing TSH secretion as needed to maintain proper levels of T4 and T3.

The sphenoid bone is a complex, irregularly shaped bone located in the middle cranial fossa and forms part of the base of the skull. It articulates with several other bones, including the frontal, parietal, temporal, ethmoid, palatine, and zygomatic bones. The sphenoid bone has two main parts: the body and the wings.

The body of the sphenoid bone is roughly cuboid in shape and contains several important structures, such as the sella turcica, which houses the pituitary gland, and the sphenoid sinuses, which are air-filled cavities within the bone. The greater wings of the sphenoid bone extend laterally from the body and form part of the skull's lateral walls. They contain the superior orbital fissure, through which important nerves and blood vessels pass between the cranial cavity and the orbit of the eye.

The lesser wings of the sphenoid bone are thin, blade-like structures that extend anteriorly from the body and form part of the floor of the anterior cranial fossa. They contain the optic canal, which transmits the optic nerve and ophthalmic artery between the brain and the orbit of the eye.

Overall, the sphenoid bone plays a crucial role in protecting several important structures within the skull, including the pituitary gland, optic nerves, and ophthalmic arteries.

Placental hormones are a type of hormones that are produced by the placenta, an organ that develops in the uterus during pregnancy. These hormones play a crucial role in maintaining and supporting a healthy pregnancy. Some of the key placental hormones include:

1. Human Chorionic Gonadotropin (hCG): This hormone is produced after implantation and is detected in the urine or blood to confirm pregnancy. It maintains the corpus luteum, which produces progesterone during early pregnancy.
2. Progesterone: This hormone is critical for preparing the uterus for pregnancy and maintaining the pregnancy. It suppresses maternal immune response to prevent rejection of the developing embryo/fetus.
3. Estrogen: This hormone plays a vital role in the growth and development of the fetal brain, as well as promoting the growth of the uterus and mammary glands during pregnancy.
4. Human Placental Lactogen (hPL): This hormone stimulates maternal metabolism to provide nutrients for the developing fetus and helps prepare the breasts for lactation.
5. Relaxin: This hormone relaxes the pelvic ligaments and softens and widens the cervix in preparation for childbirth.

These hormones work together to support fetal growth, maintain pregnancy, and prepare the mother's body for childbirth and lactation.

The pituitary-adrenal system, also known as the hypothalamic-pituitary-adrenal (HPA) axis, is a complex set of interactions between the hypothalamus, the pituitary gland, and the adrenal glands. This system plays a crucial role in the body's response to stress through the release of hormones that regulate various physiological processes.

The hypothalamus, located within the brain, receives information from the nervous system about the internal and external environment and responds by releasing corticotropin-releasing hormone (CRH) and vasopressin. These hormones then travel to the anterior pituitary gland, where they stimulate the release of adrenocorticotropic hormone (ACTH).

ACTH is transported through the bloodstream to the adrenal glands, which are located on top of the kidneys. The adrenal glands consist of two parts: the outer cortex and the inner medulla. ACTH specifically targets the adrenal cortex, causing it to release cortisol and other glucocorticoids, as well as androgens such as dehydroepiandrosterone (DHEA).

Cortisol has numerous effects on metabolism, immune function, and cardiovascular regulation. It helps regulate blood sugar levels, suppresses the immune system, and aids in the breakdown of fats, proteins, and carbohydrates to provide energy during stressful situations. DHEA can be converted into male and female sex hormones (androgens and estrogens) in various tissues throughout the body.

The pituitary-adrenal system is tightly regulated through negative feedback mechanisms. High levels of cortisol, for example, inhibit the release of CRH and ACTH from the hypothalamus and pituitary gland, respectively, thereby limiting further cortisol production. Dysregulation of this system has been implicated in several medical conditions, including Cushing's syndrome (overproduction of cortisol) and Addison's disease (underproduction of cortisol).

Aging is a complex, progressive and inevitable process of bodily changes over time, characterized by the accumulation of cellular damage and degenerative changes that eventually lead to increased vulnerability to disease and death. It involves various biological, genetic, environmental, and lifestyle factors that contribute to the decline in physical and mental functions. The medical field studies aging through the discipline of gerontology, which aims to understand the underlying mechanisms of aging and develop interventions to promote healthy aging and extend the human healthspan.

Thyrotropin, also known as thyroid-stimulating hormone (TSH), is a hormone produced and released by the anterior pituitary gland. It plays a crucial role in regulating the function of the thyroid gland by stimulating the production and release of thyroid hormones, triiodothyronine (T3) and thyroxine (T4).

The TSH molecule is composed of two subunits: alpha and beta. The alpha subunit is common to several pituitary hormones, including TSH, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and human chorionic gonadotropin (hCG). In contrast, the beta subunit is unique to each hormone, determining its specific biological activity.

Therefore, 'Thyrotropin, beta Subunit' refers to the distinct portion of the TSH molecule that confers its thyroid-stimulating properties and allows it to be identified and measured separately from other pituitary hormones sharing the common alpha subunit. Beta-subunit assays are sometimes used in clinical settings to evaluate thyroid function, as they can provide information about TSH levels independent of the common alpha subunit.

Thyroid hormone receptors (THRs) are nuclear receptor proteins that bind to thyroid hormones and mediate their effects in the body. There are two main types of THRs, referred to as THRα and THRβ.

THRα is a subtype of thyroid hormone receptor that is primarily expressed in tissues such as the heart, skeletal muscle, and brown adipose tissue. It plays an important role in regulating metabolism, growth, and development in these tissues. THRα has two subtypes, THRα1 and THRα2, which have different functions and are expressed in different tissues.

THRα1 is the predominant form of THRα and is found in many tissues, including the heart, skeletal muscle, and brown adipose tissue. It regulates genes involved in metabolism, growth, and development, and has been shown to play a role in regulating heart rate and contractility.

THRα2, on the other hand, is primarily expressed in the brain and pituitary gland, where it regulates the production of thyroid-stimulating hormone (TSH). THRα2 is unable to bind to thyroid hormones, but can form heterodimers with THRα1 or THRβ1, which allows it to modulate their activity.

Overall, THRα plays an important role in regulating various physiological processes in the body, and dysregulation of THRα function has been implicated in a number of diseases, including heart disease, muscle wasting, and neurological disorders.

Pancreatic hormones are chemical messengers produced and released by the pancreas, a gland located in the abdomen. The two main types of pancreatic hormones are insulin and glucagon, which are released by specialized cells called islets of Langerhans.

Insulin is produced by beta cells and helps regulate blood sugar levels by allowing cells in the body to take in sugar (glucose) from the bloodstream. It also helps the body store excess glucose in the liver for later use.

Glucagon is produced by alpha cells and has the opposite effect of insulin. When blood sugar levels are low, glucagon stimulates the release of stored glucose from the liver to raise blood sugar levels.

Together, insulin and glucagon help maintain balanced blood sugar levels and are essential for the proper functioning of the body's metabolism. Other hormones produced by the pancreas include somatostatin, which regulates the release of insulin and glucagon, and gastrin, which stimulates the production of digestive enzymes in the stomach.

Endorphins are a type of neurotransmitter, which are chemicals that transmit signals in the nervous system and brain. The term "endorphin" comes from "endogenous morphine," reflecting the fact that these substances are produced naturally within the body and have effects similar to opiate drugs like morphine.

Endorphins are released in response to stress or pain, but they also occur naturally during exercise, excitement, laughter, love, and orgasm. They work by interacting with the opiate receptors in the brain to reduce the perception of pain and promote feelings of pleasure and well-being. Endorphins also play a role in regulating various physiological processes, including appetite, mood, and sleep.

In summary, endorphins are natural painkillers and mood elevators produced by the body in response to stress, pain, or enjoyable activities.

Insect hormones are chemical messengers that regulate various physiological and behavioral processes in insects. They are produced and released by endocrine glands and organs, such as the corpora allata, prothoracic glands, and neurosecretory cells located in the brain. Insect hormones play crucial roles in the regulation of growth and development, reproduction, diapause (a state of dormancy), metamorphosis, molting, and other vital functions. Some well-known insect hormones include juvenile hormone (JH), ecdysteroids (such as 20-hydroxyecdysone), and neuropeptides like the brain hormone and adipokinetic hormone. These hormones act through specific receptors, often transmembrane proteins, to elicit intracellular signaling cascades that ultimately lead to changes in gene expression, cell behavior, or organ function. Understanding insect hormones is essential for developing novel strategies for pest management and control, as well as for advancing our knowledge of insect biology and evolution.

Testicular hormones, also known as androgens, are a type of sex hormone primarily produced in the testes of males. The most important and well-known androgen is testosterone, which plays a crucial role in the development of male reproductive system and secondary sexual characteristics. Testosterone is responsible for the growth and maintenance of male sex organs, such as the testes and prostate, and it also promotes the development of secondary sexual characteristics like facial hair, deep voice, and muscle mass.

Testicular hormones are produced and regulated by a feedback system involving the hypothalamus and pituitary gland in the brain. The hypothalamus produces gonadotropin-releasing hormone (GnRH), which stimulates the pituitary gland to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). LH stimulates the testes to produce testosterone, while FSH works together with testosterone to promote sperm production.

In addition to their role in male sexual development and function, testicular hormones also have important effects on other bodily functions, such as bone density, muscle mass, red blood cell production, mood, and cognitive function.

The sphenoid sinuses are air-filled spaces located within the sphenoid bone, which is one of the bones that make up the skull base. These sinuses are located deep inside the skull, behind the eyes and nasal cavity. They are paired and separated by a thin bony septum, and each one opens into the corresponding nasal cavity through a small opening called the sphenoethmoidal recess. The sphenoid sinuses vary greatly in size and shape between individuals. They develop during childhood and continue to grow until early adulthood. The function of the sphenoid sinuses, like other paranasal sinuses, is not entirely clear, but they may contribute to reducing the weight of the skull, resonating voice during speech, and insulating the brain from trauma.

Orchiectomy is a surgical procedure where one or both of the testicles are removed. It is also known as castration. This procedure can be performed for various reasons, including the treatment of testicular cancer, prostate cancer, or other conditions that may affect the testicles. It can also be done to reduce levels of male hormones in the body, such as in the case of transgender women undergoing gender affirming surgery. The specific medical definition may vary slightly depending on the context and the extent of the procedure.

A missense mutation is a type of point mutation in which a single nucleotide change results in the substitution of a different amino acid in the protein that is encoded by the affected gene. This occurs when the altered codon (a sequence of three nucleotides that corresponds to a specific amino acid) specifies a different amino acid than the original one. The function and/or stability of the resulting protein may be affected, depending on the type and location of the missense mutation. Missense mutations can have various effects, ranging from benign to severe, depending on the importance of the changed amino acid for the protein's structure or function.

Estrus is a term used in veterinary medicine to describe the physiological and behavioral state of female mammals that are ready to mate and conceive. It refers to the period of time when the female's reproductive system is most receptive to fertilization.

During estrus, the female's ovaries release one or more mature eggs (ovulation) into the fallopian tubes, where they can be fertilized by sperm from a male. This phase of the estrous cycle is often accompanied by changes in behavior and physical appearance, such as increased vocalization, restlessness, and swelling of the genital area.

The duration and frequency of estrus vary widely among different species of mammals. In some animals, such as dogs and cats, estrus occurs regularly at intervals of several weeks or months, while in others, such as cows and mares, it may only occur once or twice a year.

It's important to note that the term "estrus" is not used to describe human reproductive physiology. In humans, the equivalent phase of the menstrual cycle is called ovulation.

Invertebrate hormones refer to the chemical messengers that regulate various physiological processes in invertebrate animals, which include insects, mollusks, worms, and other animals without a backbone. These hormones are produced by specialized endocrine cells or glands and released into the bloodstream to target organs, where they elicit specific responses that help control growth, development, reproduction, metabolism, and behavior.

Examples of invertebrate hormones include:

1. Ecdysteroids: These are steroid hormones found in arthropods such as insects and crustaceans. They regulate molting (ecdysis) and metamorphosis by stimulating the growth and differentiation of new cuticle layers.
2. Juvenile hormone (JH): This is a sesquiterpenoid hormone produced by the corpora allata glands in insects. JH plays a crucial role in maintaining the juvenile stage, regulating reproduction, and controlling diapause (a period of suspended development during unfavorable conditions).
3. Neuropeptides: These are short chains of amino acids that act as hormones or neurotransmitters in invertebrates. They regulate various functions such as feeding behavior, growth, reproduction, and circadian rhythms. Examples include the neuropeptide F (NPF), which controls food intake and energy balance, and the insulin-like peptides (ILPs) that modulate metabolism and growth.
4. Molluscan cardioactive peptides: These are neuropeptides found in mollusks that regulate heart function by controlling heart rate and contractility. An example is FMRFamide, which has been identified in various mollusk species and influences several physiological processes, including feeding behavior, muscle contraction, and reproduction.
5. Vertebrate-like hormones: Some invertebrates produce hormones that are structurally and functionally similar to those found in vertebrates. For example, some annelids (segmented worms) and cephalopods (squid and octopus) have insulin-like peptides that regulate metabolism and growth, while certain echinoderms (starfish and sea urchins) produce steroid hormones that control reproduction.

In summary, invertebrates utilize various types of hormones to regulate their physiological functions, including neuropeptides, cardioactive peptides, insulin-like peptides, and vertebrate-like hormones. These hormones play crucial roles in controlling growth, development, reproduction, feeding behavior, and other essential processes that maintain homeostasis and ensure survival. Understanding the mechanisms of hormone action in invertebrates can provide valuable insights into the evolution of hormonal systems and their functions across different animal taxa.

Beta-endorphins are naturally occurring opioid peptides that are produced in the brain and other parts of the body. They are synthesized from a larger precursor protein called proopiomelanocortin (POMC) and consist of 31 amino acids. Beta-endorphins have potent analgesic effects, which means they can reduce the perception of pain. They also play a role in regulating mood, emotions, and various physiological processes such as immune function and hormonal regulation.

Beta-endorphins bind to opioid receptors in the brain and other tissues, leading to a range of effects including pain relief, sedation, euphoria, and reduced anxiety. They are released in response to stress, physical activity, and certain physiological conditions such as pregnancy and lactation. Beta-endorphins have been studied for their potential therapeutic uses in the treatment of pain, addiction, and mood disorders. However, more research is needed to fully understand their mechanisms of action and potential side effects.

Organ size refers to the volume or physical measurement of an organ in the body of an individual. It can be described in terms of length, width, and height or by using specialized techniques such as imaging studies (like CT scans or MRIs) to determine the volume. The size of an organ can vary depending on factors such as age, sex, body size, and overall health status. Changes in organ size may indicate various medical conditions, including growths, inflammation, or atrophy.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

Diabetes Insipidus is a medical condition characterized by the excretion of large amounts of dilute urine (polyuria) and increased thirst (polydipsia). It is caused by a deficiency in the hormone vasopressin (also known as antidiuretic hormone or ADH), which regulates the body's water balance.

In normal physiology, vasopressin is released from the posterior pituitary gland in response to an increase in osmolality of the blood or a decrease in blood volume. This causes the kidneys to retain water and concentrate the urine. In Diabetes Insipidus, there is either a lack of vasopressin production (central diabetes insipidus) or a decreased response to vasopressin by the kidneys (nephrogenic diabetes insipidus).

Central Diabetes Insipidus can be caused by damage to the hypothalamus or pituitary gland, such as from tumors, trauma, or surgery. Nephrogenic Diabetes Insipidus can be caused by genetic factors, kidney disease, or certain medications that interfere with the action of vasopressin on the kidneys.

Treatment for Diabetes Insipidus depends on the underlying cause. In central diabetes insipidus, desmopressin, a synthetic analogue of vasopressin, can be administered to replace the missing hormone. In nephrogenic diabetes insipidus, treatment may involve addressing the underlying kidney disease or adjusting medications that interfere with vasopressin action. It is important for individuals with Diabetes Insipidus to maintain adequate hydration and monitor their fluid intake and urine output.

Vasoactive Intestinal Peptide (VIP) is a 28-amino acid polypeptide hormone that has potent vasodilatory, secretory, and neurotransmitter effects. It is widely distributed throughout the body, including in the gastrointestinal tract, where it is synthesized and released by nerve cells (neurons) in the intestinal mucosa. VIP plays a crucial role in regulating various physiological functions such as intestinal secretion, motility, and blood flow. It also has immunomodulatory effects and may play a role in neuroprotection. High levels of VIP are found in the brain, where it acts as a neurotransmitter or neuromodulator and is involved in various cognitive functions such as learning, memory, and social behavior.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

Beta-lipotropin (β-LPH) is a 91-amino acid polypeptide hormone that is derived from proopiomelanocortin (POMC), along with other bioactive peptides such as adrenocorticotropic hormone (ACTH), melanocyte-stimulating hormones (MSH), and β-endorphin. It is produced and released by the anterior pituitary gland in response to stress or corticotropin-releasing hormone (CRH) stimulation.

β-Lipotropin has been found to have several physiological functions, including the regulation of lipid metabolism, appetite control, and pain perception. It also exhibits opioid activity due to its ability to bind to opioid receptors in the brain, although its potency is much lower compared to other endogenous opioids like β-endorphin.

In addition to its role as a hormone, β-lipotropin has been studied for its potential therapeutic applications, particularly in the treatment of obesity and addiction. However, further research is needed to fully understand its mechanisms and clinical efficacy.

Cyclic adenosine monophosphate (cAMP) is a key secondary messenger in many biological processes, including the regulation of metabolism, gene expression, and cellular excitability. It is synthesized from adenosine triphosphate (ATP) by the enzyme adenylyl cyclase and is degraded by the enzyme phosphodiesterase.

In the body, cAMP plays a crucial role in mediating the effects of hormones and neurotransmitters on target cells. For example, when a hormone binds to its receptor on the surface of a cell, it can activate a G protein, which in turn activates adenylyl cyclase to produce cAMP. The increased levels of cAMP then activate various effector proteins, such as protein kinases, which go on to regulate various cellular processes.

Overall, the regulation of cAMP levels is critical for maintaining proper cellular function and homeostasis, and abnormalities in cAMP signaling have been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Iodide peroxidase, also known as iodide:hydrogen peroxide oxidoreductase, is an enzyme that belongs to the family of oxidoreductases. Specifically, it is a peroxidase that uses iodide as its physiological reducing substrate. This enzyme catalyzes the oxidation of iodide by hydrogen peroxide to produce iodine, which plays a crucial role in thyroid hormone biosynthesis.

The systematic name for this enzyme is iodide:hydrogen-peroxide oxidoreductase (iodinating). It is most commonly found in the thyroid gland, where it helps to produce and regulate thyroid hormones by facilitating the iodination of tyrosine residues on thyroglobulin, a protein produced by the thyroid gland.

Iodide peroxidase requires a heme cofactor for its enzymatic activity, which is responsible for the oxidation-reduction reactions it catalyzes. The enzyme's ability to iodinate tyrosine residues on thyroglobulin is essential for the production of triiodothyronine (T3) and thyroxine (T4), two critical hormones that regulate metabolism, growth, and development in mammals.

These mutations can occur in the genes coding for GnRH, LH, and FSH or their receptors. Depending on which hormone and receptor ... The anterior portion of the pituitary gland produces luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the ... GnRH travels down the anterior portion of the pituitary via the hypophyseal portal system and binds to receptors on the ... Haasl RJ, Ahmadi MR, Meethal SV, Gleason CE, Johnson SC, Asthana S, Bowen RL, Atwood CS (2008). "A luteinizing hormone receptor ...
They act on specific membrane receptors. They are glycoproteins. Then you have the signal. They stimulate release of pituitary ... Hormones of the hypothalamus, Hormones of the pituitary gland, Hormones of the hypothalamus-pituitary axis). ... There is a pituitary portal system, with which the hormones are transported. These hormones are prolactin, growth hormone, TSH ... Hypothalamic-pituitary hormones are hormones that are produced by the hypothalamus and pituitary gland. Although the organs in ...
Hypothalamic-pituitary-prolactin axis Lin, S. H. (2008). "Prolactin-Releasing Peptide". Orphan G Protein-Coupled Receptors and ... Prolactin-releasing hormone, also known as PRLH, is a hypothetical human hormone or hormone releasing factor. Existence of this ... v t e (Human hormones, All stub articles, Molecular and cellular biology stubs). ... such as thyrotropin-releasing hormone, oxytocin, vasoactive intestinal peptide and estrogen) those have primary functions other ...
August 1996). "A receptor in pituitary and hypothalamus that functions in growth hormone release". Science. 273 (5277): 974-977 ... The ghrelin receptor GHS-R1a (a splice-variant of the growth hormone secretagogue receptor, with the GHS-R1b splice being ... Ghrelin was discovered after the ghrelin receptor (called growth hormone secretagogue type 1A receptor or GHS-R) was determined ... Ghrelin stimulates brain structures having a specific receptor - the growth hormone secretagogue receptor 1A (GHSR-1A). Ghrelin ...
"GABA acts directly on cells of pituitary pars intermedia to alter hormone output". Nature. 301 (5902): 706-7. Bibcode:1983Natur ... GABAA receptors are ligand-gated ion channels (also known as ionotropic receptors); whereas GABAB receptors are G protein- ... Over-excitation of this receptor induces receptor remodeling and the eventual invagination of the GABA receptor. As a result, ... Members of this superfamily, which includes nicotinic acetylcholine receptors, GABAA receptors, glycine and 5-HT3 receptors, ...
"Pituitary adenomas of patients with acromegaly express thyrotropin-releasing hormone receptor messenger RNA: cloning and ... Thyrotropin-releasing hormone receptor (TRHR) is a G protein-coupled receptor which binds thyrotropin-releasing hormone. The ... "Thyrotropin-Releasing Hormone Receptors". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and ... Receptors,+Thyrotropin-Releasing+Hormone at the U.S. National Library of Medicine Medical Subject Headings (MeSH) v t e (CS1 ...
... expressed in the pituitary, encodes a receptor for growth-hormone-releasing hormone. Binding of this hormone to the receptor ... The growth-hormone-releasing hormone receptor (GHRHR) is a G-protein-coupled receptor that binds growth hormone-releasing ... Mayo KE (Oct 1992). "Molecular cloning and expression of a pituitary-specific receptor for growth hormone-releasing hormone". ... GHRHR is distinct from the growth hormone secretagogue receptor (also known as the ghrelin receptor), where growth hormone ...
... followed by permanent blockage of the GnRH pituitary receptor) LH is available mixed with FSH in the form of menotropin, and ... Peptide hormones, Sex hormones, Human hormones, Hormones of the hypothalamus-pituitary-gonad axis, Anterior pituitary hormones) ... Luteinizing hormone (LH, also known as luteinising hormone, lutropin and sometimes lutrophin) is a hormone produced by ... Luteinizing hormone receptors are located in areas of the brain associated with cognitive function. The role of LH role in the ...
Resistance to thyroid hormone: Feedback loop interrupted on the level of pituitary thyroid hormone receptors. Standard ... Thyroid hormone exerts negative feedback control over the hypothalamus as well as anterior pituitary, thus controlling the ... The pituitary gland secretes thyrotropin (TSH; Thyroid Stimulating Hormone) that stimulates the thyroid to secrete thyroxine ( ... Hoermann R, Midgley JE, Larisch R, Dietrich JW (2012). "Is pituitary TSH an adequate measure of thyroid hormone-controlled ...
... and pituitary. In the pituitary, CRF1 stimulation triggers the activation of the POMC gene, which in turn causes the release of ... Corticotropin-releasing hormone Corticotropin-releasing hormone receptor Corticotropin-releasing hormone antagonist Antalarmin ... Corticotropin-releasing+hormone+receptors at the U.S. National Library of Medicine Medical Subject Headings (MeSH) CRF+receptor ... Corticotropin-releasing hormone receptor 1 has been shown to interact with Corticotropin-releasing hormone and urocortin. ...
... receptors of human pituitary gland". J. Endocrinol. Invest. 24 (1): RC1-3. doi:10.1007/bf03343800. PMID 11227737. S2CID ... Deghenghi R, Papotti M, Ghigo E, Muccioli G (2001). "Cortistatin, but not somatostatin, binds to growth hormone secretagogue ( ... Robas N, Mead E, Fidock M (2004). "MrgX2 is a high potency cortistatin receptor expressed in dorsal root ganglion". J. Biol. ... 2003). "Cortistatin rather than somatostatin as a potential endogenous ligand for somatostatin receptors in the human immune ...
Hypothalamic-pituitary-prolactin axis Male lactation Prolactin modulator Prolactin receptor Prolactin-releasing hormone ... Anterior pituitary hormones, Breastfeeding, Galactagogues, Hormones of the hypothalamic-pituitary-prolactin axis, Hormones of ... The hormone acts in endocrine, autocrine, and paracrine manners through the prolactin receptor and numerous cytokine receptors ... Human prolactin receptors are insensitive to mouse prolactin. Prolactin levels may be checked as part of a sex hormone workup, ...
... is a gonadotropin-releasing hormone (GnRH) analogue acting as an agonist at pituitary GnRH receptors. Agonism of ... "Hormone Therapy in Gender Dysphoria" (PDF). NHS Guideline. Table 1 "Hormone Therapy in Gender Dysphoria" (PDF). NHS Guideline. ... GnRH receptors initially results in the stimulation of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) ... pituitary GnRH receptors become desensitised after several weeks of continuous leuprorelin therapy. This protracted ...
"An Autocrine Role for Pituitary GABA: Activation of GABA-B Receptors and Regulation of Growth Hormone Levels". ... The third receptor is the δ-opioid receptor (DOR). The delta receptor is the least studied out of the 3 main opioid receptors. ... Opioid receptors are specialized pain blocking receptors. They bind a wide range of hormones, peptides, and much more. Although ... The μ-opioid receptor is a G-protein coupled receptor. When the μ-opioid receptor is activated, it causes pain relief, euphoria ...
... from the anterior pituitary-body. These hormones are responsible for the synthesis of steroid sex hormones (testosterone in men ... GnRH agonists are a group of drugs intended to activate GnRH receptors in the anterior pituitary gland. They are synthesized by ... The melanocortin receptor agonist proposes to activate multiple receptor subtypes nonselectively, with the highest affinity ... It compiles a serotonin 1A receptor agonist and a serotonin 2A receptor antagonist. and is an antidepressant that was ...
Prolactin Growth hormone Human placental lactogen Placental growth hormone S179D-hPRL Prolactin receptor antagonists such as ... "Use of prolactin receptor antagonist to better understand prolactin regulation of pituitary homeostasis". Neuroendocrinology. ... It is the receptor for prolactin (PRL). The PRLR can also bind to and be activated by growth hormone (GH) and human placental ... The prolactin receptor (PRLR) is a membrane-bound protein of the cytokine receptor superfamily. In humans, it is encoded by a ...
At the pituitary, GnRH stimulates the synthesis and secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH ... Kakar SS, Jennes L (November 1995). "Expression of gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor ... Luteinizing hormone-releasing hormone (LRH, LHRH) Follicle-stimulating hormone and luteinizing hormone-releasing factor (FSH/LH ... Follicle-stimulating hormone and luteinizing hormone-releasing hormone (FSH/LH-RH) Luteinizing hormone and follicle-stimulating ...
They also regulate many hormones including pituitary, gonadal and hypothalamic hormones as well as insulin. They are also nerve ... The type II receptor is a serine/threonine receptor kinase, which catalyzes the phosphorylation of the Type I receptor. Each ... It can then either form a receptor complex with activin A receptor, type IB (ACVR1B) or with activin A receptor, type IC ( ... TGFβ superfamily ligands bind to a type II receptor, which recruits and phosphorylates a type I receptor. The type I receptor ...
The anterior pituitary in turn releases adrenocorticotropic hormone (ACTH). ACTH induces the release of corticosteroids and ... When a receptor within the body senses a stressor, a signal is sent to the anterior hypothalamus. At the reception of the ... Stress hormones influence the processes carried out in the hippocampus and amygdala which are also associated with emotional ... These stress hormones are also hindering the hippocampus from receiving enough energy by diverting glucose levels to ...
"Gonadotrophin-Releasing Hormone Receptors: GnRH receptor". IUPHAR Database of Receptors and Ion Channels. International Union ... G-protein coupled receptor (GPCR) family. It is expressed on the surface of pituitary gonadotrope cells as well as lymphocytes ... This gene encodes the receptor for type 1 gonadotropin-releasing hormone. This receptor is a member of the seven-transmembrane ... Bédécarrats GY, Kaiser UB (2007). "Mutations in the human gonadotropin-releasing hormone receptor: insights into receptor ...
The drug works by blocking the action of gonadotropin-releasing hormone (GnRH) upon the pituitary, thus rapidly suppressing the ... Gonadotropin-releasing hormone receptor § Antagonists "Ganirelix Theramex (Theramex Australia Pty Ltd)". Therapeutic Goods ... Ganirelix competitively blocks GnRH receptors on the pituitary gonadotroph, quickly resulting in the suppression of ... Ganirelix has a significantly higher receptor binding affinity (Kd = 0.4 nM) than GnRH (Kd = 3.6 nM). When ganirelix is given ...
"Aberrant alternative splicing of thyroid hormone receptor in a TSH-secreting pituitary tumor is a mechanism for hormone ... NCOR2 is also referred to as a silencing mediator for retinoid or thyroid-hormone receptors (SMRT) or T3 receptor-associating ... a silencing mediator for retinoid and thyroid hormone receptors-extended isoform that is more related to the nuclear receptor ... "Ligand-independent repression by the thyroid hormone receptor mediated by a nuclear receptor co-repressor". Nature. 377 (6548 ...
Human hormones, Hormones of the hypothalamus-pituitary-thyroid axis, Hormones of the thyroid gland). ... 3,5-T2 is an active thyroid hormone. It stimulates the TR-beta receptor for thyroid hormones and thus increases energy ... 3,5-Diiodothyronine (3,5-T2) is an active thyroid hormone within the class of iodothyronines. It has two iodine atoms at ... This could explain why patients with low T3 syndrome don't benefit from substitution therapy with thyroid hormones. Goglia F ( ...
"Aberrant alternative splicing of thyroid hormone receptor in a TSH-secreting pituitary tumor is a mechanism for hormone ... "Thyroid hormone receptor mutants that cause resistance to thyroid hormone. Evidence for receptor competition for DNA sequences ... Thyroid hormone receptor beta (TR-beta) also known as nuclear receptor subfamily 1, group A, member 2 (NR1A2), is a nuclear ... The protein encoded by this gene is a nuclear hormone receptor for triiodothyronine. It is one of the several receptors for ...
It is a growth hormone secretagogue receptor (ghrelin receptor) agonist causing release of growth hormone from the pituitary ... Macimorelin acetate, the salt formulation, is a synthetic growth hormone secretagogue receptor agonist. ... As of December 2017, it became FDA-approved as a method to diagnose growth hormone deficiency. Traditionally, growth hormone ... Ghrelin receptor agonists, Growth hormone secretagogues, Tryptamines, Peptides, All stub articles, Systemic hormonal ...
"Isoform-specific thyroid hormone receptor antibodies detect multiple thyroid hormone receptors in rat and human pituitaries". ... "Characterization of a third human thyroid hormone receptor coexpressed with other thyroid hormone receptors in several tissues ... "Heterodimerization among thyroid hormone receptor, retinoic acid receptor, retinoid X receptor, chicken ovalbumin upstream ... Thyroid hormone receptor alpha (TR-alpha) also known as nuclear receptor subfamily 1, group A, member 1 (NR1A1), is a nuclear ...
V1 receptors are found in various sites around the body. The major points include the CNS, Liver, Anterior Pituitary, Muscle ( ... Felypressin is a non-catecholamine vasoconstrictor that is chemically related to vasopressin, the posterior pituitary hormone. ... Felypressin is a Vasopressin 1 agonist, and will thus have effects at all Arginine vasopressin receptor 1As. It will, however, ...
The pituitary synthesizes and secretes thyroid-stimulating hormone (TSH). TSH, in turn, stimulates production of the thyroid ... In Igsf1 deficient mice, the receptor for TRH is downregulated in the pituitary. This decrease could explain, at least in part ... TSH secretion is controlled by thyrotropin-releasing hormone (TRH), which is released by neurons in the hypothalamus of the ... How the loss of IGSF1 causes a decrease in TRH receptors is presently unknown. GRCh38: Ensembl release 89: ENSG00000147255 - ...
The gonadotropin receptors are a group of receptors that bind a group of pituitary hormones called gonadotropins. They include ... GnRH receptor Sex hormone receptor v t e (G protein-coupled receptors, Gonadotropin-releasing hormone and gonadotropins, Signal ... Follicle-stimulating hormone receptor (FSHR) - binds follicle-stimulating hormone (FSH) Luteinizing hormone receptor (LHR) - ... binds luteinizing hormone (LH) and human chorionic gonadotropin (hCG) ...
... pituitary adenoma), or other pituitary disorders). The diagnosis may involve identifying a mutation of the thyroid receptor, ... More than 1000 individuals have been identified with thyroid hormone resistance, of which 85% had thyroid hormone beta receptor ... Refetoff S, Dumitrescu AM (2007). "Syndromes of reduced sensitivity to thyroid hormone: genetic defects in hormone receptors, ... Hypothalamus secretes a hormone called thyrotropin releasing hormone (TRH) which in turn release thyroid stimulating hormone ( ...
Receptors, Pituitary Hormone-Regulating Hormone*Receptors, Pituitary Hormone-Regulating Hormone. *Receptors, Pituitary Hormone ... Receptors, Pituitary Hormone-Releasing Hormone*Receptors, Pituitary Hormone-Releasing Hormone. *Receptors, Pituitary Hormone ... Receptors, Pituitary Hormone Release Inhibiting Hormones*Receptors, Pituitary Hormone Release Inhibiting Hormones ... Pituitary Hormone-Regulating Hormone" by people in Profiles.. * Expression of growth hormone-releasing hormone receptors in ...
These gonadal hormones are produced by the hypothalamic-pituitary-gonadal (HPG) axis and have been shown to determine sex ... Although these actions of gonadal hormones are well supported, the possibility that sex chromosomes similarly influence HPA ... and this difference has largely been attributed to modulation by the gonadal hormones testosterone and estradiol. ... The hypothalamic-pituitary-adrenal (HPA) axis, a neuroendocrine network that controls hormonal responses to internal and ...
These mutations can occur in the genes coding for GnRH, LH, and FSH or their receptors. Depending on which hormone and receptor ... The anterior portion of the pituitary gland produces luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the ... GnRH travels down the anterior portion of the pituitary via the hypophyseal portal system and binds to receptors on the ... Haasl RJ, Ahmadi MR, Meethal SV, Gleason CE, Johnson SC, Asthana S, Bowen RL, Atwood CS (2008). "A luteinizing hormone receptor ...
... P. Limonta. Primo. ;D ... Effects of aging on pituitary and testicular luteinizing hormone-releasing hormone receptors in the rat / P. Limonta, D. Dondi ... Rats, Inbred Strains; Rats; Animals; Testosterone; Receptors, LH; Pituitary Gland; Luteinizing Hormone; Testis; Aging; Male ... occurring in old animals is reflected by modifications of luteinizing hormone-releasing hormone (LHRH) receptors at the level ...
... hormone stimulates prolactin secretion through melanocortin 3-receptors expressed in mammotrophs in themouse pituitary. In: ... T1 - Melanocyte-stimulating hormone stimulates prolactin secretion through melanocortin 3-receptors expressed in mammotrophs in ... Melanocyte-stimulating hormone stimulates prolactin secretion through melanocortin 3-receptors expressed in mammotrophs in ... Melanocyte-stimulating hormone stimulates prolactin secretion through melanocortin 3-receptors expressed in mammotrophs in ...
Gonadal steroid hormone receptors and sex differences in the hypothalamo-pituitary-adrenal axis. Horm. Behav. 28, 464-476. doi ... CRH receptors, guanylate cyclase-C receptors, neurokinin-1 receptors, neurokinin-3 receptors, nociception/orphanin FQ receptors ... neurokinin-1 receptors, serotonin receptors, transient receptor potential cation channel subfamily V member 1 (TRPV1) receptors ... corticotropin-releasing hormone; MR, mineralocorticoid receptor; GR, glucocorticoid receptor; CeA, central nucleus of the ...
... reduces the release of gonadotropins from the pituitary. Estradiol increases the synthesis of DNA, RNA, and many proteins in ... Hormonal/endocrine therapies: gonadotropin-releasing hormone (GnRH) agonists, luteinizing hormone-releasing hormone (LHRH) ... Parathyroid Hormone Analogs. Class Summary. Parathyroid hormone (PTH) is the primary regulator of calcium and phosphate ... Selective Estrogen Receptor Modulator. Class Summary. Selective estrogen receptor modulators (SERMs) affect some of the ...
Pegvisomant: a growth hormone receptor antagonist used in the treatment of acromegaly. Pituitary. 2017 Feb. 20(1):129-35. [QxMD ... Growth hormone and insulinlike growth factor. GH is necessary for normal linear growth. Its secretion from the pituitary gland ... Growth hormone measurements in the diagnosis and monitoring of acromegaly. Pituitary. 2007. 10(2):165-72. [QxMD MEDLINE Link]. ... Growth hormone-secreting pituitary adenomas in childhood and adolescence: features and results of transnasal surgery. ...
Desensitization, trafficking, and resensitization of the pituitary thyrotropin-releasing hormone receptor.; Frontiers in ... the receptor changes conformation, activates Gq, and becomes phosphorylated by specific receptor kinases; the phospho-receptor ... siRNA screen identifies the phosphatase acting on the G protein-coupled thyrotropin-releasing hormone receptor.; ACS chemical ... to study signal pathways for a hypothalamic peptide hormone, TRH, which acts via a G protein coupled receptor to increase ...
Pituitary. Adrenals. Thyroid and Thyroid Hormone Receptor. Adipose Tissue. Cardiovascular System. Lung. Lacrimal and Salivary ... Additional Immunoglobulin-related Receptors (includes NK cell receptors). Butyrophilin Family. Interleukins and Their Receptors ... Ephrins and Ephrin Receptors. Epidermal Growth Factor. Fibroblast Growth Factors. TGF-β Family. Growth Hormone and Related ... Toll-like Receptors. Pyrin and Associated Functions. Complement. Fc Receptors. MS4 Family. Superoxide Pathway. HLA and Related ...
In conclusion, the association of the chronic stress with sex hormone depletion results in disturbances of the SC Cx expression ... Gonadal steroid hormone receptors and sex differences in the hypothalamo-pituitary-adrenal axis. Horm. Behav. 1994, 28, 464-476 ... Sex-specific chronic stress response at the level of adrenal gland modified sexual hormone and leptin receptors. Croat. Med. J. ... Hormones in general play an important role in the function of nerve tissue. It is reported that sex hormones exert a ...
Pituitary resistance to suppressive effect of thyroid hormone due to a mutation in the T3 receptor ... The iodine hormone exerts its action on receptors on the nucleus in cells. T3 binds to the nuclear receptor (TR) and combines ... The pituitary senses there is too much hormone production and is shut off. When it senses not enough thyroid hormone ... as T4 in binding to a receptor that exerts the action as receptor to the thyroid hormone. If taken by mouth T3 is 3 to 4 times ...
Thyrostimulin, a heterodimer of two new human glycoprotein hormone subunits, activates the thyroid-stimulating hormone receptor ... The expression of thyrostimulin in the anterior pituitary known to express TSH receptors suggested a paracrine mechanism. The ... Thyrostimulin, a heterodimer of two new human glycoprotein hormone subunits, activates the thyroid-stimulating hormone receptor ... activated human TSH receptors, but not LH and FSH receptors, and showed high affinity to TSH receptors in a radioligand ...
Hyperthyroidism can occur in teenagers with an excess of thyroid hormones in the bloodstream. It affects how the body uses ... Genetics: a change in the thyroid-stimulating hormone (TSH) receptor gene that switches it on permanently ... Growths: a tumor that causes the pituitary gland to make too much TSH ... If excess thyroid hormone circulates in a teenagers blood for a long time, it can speed up their growth and cause puberty to ...
stimulate the pituitary glad to release hormones. *prompt the adrenal glands to make the "fight or flight" hormone adrenaline ... bind to receptors on the surface of nerve cells increasing their activity ...
Elevation of growth hormone secretagogue receptor type 1a mRNA expression in human growth hormone-secreting pituitary adenoma ... Elevation of growth hormone secretagogue receptor type 1a mRNA expression in human growth hormone-secreting pituitary adenoma ... Growth Hormone-Secreting Pituitary Adenoma:complications, Humans, Male, Middle Aged, Mutation, RNA, Messenger:metabolism, ... Effect of fluoxetine and adenosine receptor NECA agonist on G alpha q/11 protein of C6 glioma cells.. Kovárů H, Kováru F, Lisá ...
Other prognostic factors, such as histologic subtype, grade and hormone receptor status did not differ between the groups 5[see ... Progesterone receptors have been identified in the female reproductive tract, breast, pituitary, hypothalamus, and central ... Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH), and FSH through a ... Estrogens act through binding to nuclear receptors in estrogen-responsive tissues. To date, two estrogen receptors have been ...
Unlike degarelix, these therapies stimulate the natural hormones receptor on the pituitary gland. These agents also have a ... This initial stimulation of the receptors stimulate hormone-dependent tumour growth rather than inhibit it, and may lead to a ... Naturally occurring GnRH binds to the GnRH receptor on cells in the pituitary gland, triggering the production of luteinising ... Both GnRH agonists and blockers bind to this same receptor target.. Agonists work initially by stimulating release of LH and ...
Other prognostic factors such as histologic subtype, grade and hormone receptor status did not differ between the groups. ... Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and follicle stimulating ... Estrogens act through binding to nuclear receptors in estrogen-responsive tissues. To date, two estrogen receptors have been ... The hormones in ESTRATEST and ESTRATEST H.S. Tablets can pass into your milk. * about all of your medical problems. Your ...
Sermorelin binds to specific receptors in the hypothalamus and pituitary gland, triggering the release of growth hormone from ... Examples of peptide hormones include insulin, growth hormone, and thyroid-stimulating hormone. These hormones function by ... Peptide hormones. Peptide hormones are a group of signaling molecules that are secreted by endocrine glands and regulate ... It functions as an analog of growth hormone-releasing hormone (GHRH), encouraging the body to produce and release natural ...
... with selective affinity for this receptor may therefore be more effective in the treatment of hormone-secreting pituitary ... Somatostatin (SRIF), a hypothalamic inhibitor of pituitary growth hormone (GH) and thyroid-stimulating hormone (TSH) secretion ... the distribution of growth hormone pituitary cells, as well as circulating growth hormone levels, were normal. Treatment of ... Somatostatin receptor subtype specificity in human fetal pituitary cultures. Differential role of SSTR2 and SSTR5 for growth ...
It binds to growth hormone releasing factor receptors on the pituitary somatotroph cells. This binding stimulates the ... Synthetic growth hormone releasing factor analogue; given subcutaneously. Indicated for reducing excess abdominal fat in HIV- ... Tesamorelin is a synthetic analog of the hypothalamic produced peptide known as growth hormone releasing factor (GRF). ... Tesamorelin stimulates the production of growth hormone, which is known to inhibit the enzyme 11-beta-hydroxysteroid ...
Mice devoid of all known thyroid hormone receptors are viable but exhibit disorders of the pituitary-thyroid axis, growth, and ... Increased adipogenesis in bone marrow but decreased bone mineral density in mice devoid of thyroid hormone receptors. ... Retardation of post-natal development caused by a negatively acting thyroid hormone receptor alpha1. ... GH substitution reverses the growth phenotype but not the defective ossification in thyroid hormone receptor alpha 1-/-beta-/- ...
The hormone is produced by the pituitary gland and hypothalamus during exercise, as well as excitement and pain (12). ... through binding to opioid receptors in the frontal cortex and limbic region, areas involved with mood; and by interacting with ...
The major hormone regulating water metabolism in the body is vasopressin. Vasopressin is a 9-amino acid peptide that is ... Q. W. Ding, Y. Zhang, Y. Wang et al., "Functional vanilloid receptor-1 in human submandibular glands," Journal of Dental ... pituitary), and V2 (vascular, renal). Therefore, age-related dysfunction of the hypothalamic-neurohypophyseal-vasopressin axis ... Y. Zhang, X. Cong, L. Shi et al., "Activation of transient receptor potential vanilloid subtype 1 increases secretion of the ...
Other prognostic factors, such as histologic subtype, grade and hormone receptor status did not differ between the groups6 [see ... Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and follicle stimulating ... Estrogens act through binding to nuclear receptors in estrogen responsive tissues. To date, two estrogen receptors have been ... The hormone in MINIVELLE can pass into your breast milk.. Tell your healthcare provider about all the medicines you take ...
It can bind the GHRH receptors in the pituitary gland and also stimulate the release and production of the growth hormone ... The "Fragment 176-191 is a growth hormone, which is a modified version of the HGH [Human Growth Hormone] molecule. It also goes ... Sermorelin also has the same type of biological activity as the Growth Hormone-Releasing Hormone or GHRH. It can also treat GH ... This is a growth hormone-releasing peptide and has been shown to stimulate growth hormones in all animal test subjects. This ...
Pegvisomant: a growth hormone receptor antagonist used in the treatment of acromegaly. Pituitary. 2017 Feb. 20(1):129-35. [QxMD ... Growth hormone and insulinlike growth factor. GH is necessary for normal linear growth. Its secretion from the pituitary gland ... Growth hormone measurements in the diagnosis and monitoring of acromegaly. Pituitary. 2007. 10(2):165-72. [QxMD MEDLINE Link]. ... Growth hormone-secreting pituitary adenomas in childhood and adolescence: features and results of transnasal surgery. ...
Human growth hormone (HGH) plays a pivotal role during puberty. Eating a balanced diet can help to accelerate growth and ensure ... Vitamin A interacts with certain receptors in the pituitary gland, thereby increasing the release of growth hormone. Studies ... The release of HGH from the pituitary gland is controlled by two other hormones, growth hormone-releasing hormone and ... The growth hormone-releasing hormone, as its name implies, prompts the production and release of the human growth hormone. ...
  • GnRH travels down the anterior portion of the pituitary via the hypophyseal portal system and binds to receptors on the secretory cells of the adenohypophysis. (wikipedia.org)
  • the phospho-receptor binds to beta-arrestin. (rochester.edu)
  • T3 binds to the nuclear receptor (TR) and combines with another receptor (RXR) then combines with a receptor element on DNA. (cdc.gov)
  • Then, it travels to the pituitary gland, and binds to its receptors to stimulate the growth hormone release. (visualtasktips.com)
  • It's like a flow chart: You have an emotion, the emotion causes the hypothalamus to create a neuropeptide called CRF that causes the pituitary glad to secrete ACTH, which in turn binds itself to the receptors in the adrenal glands, which causes the adrenal glands to make a stress hormone, a steroid known as corticosterone. (emofree.com)
  • Relugolix is a non-peptide GnRH receptor antagonist that competitively binds to pituitary GnRH receptors, thereby reducing the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), leading to decreased serum concentrations of the ovarian sex hormones estradiol and progesterone and reduced bleeding associated with uterine fibroids. (centerwatch.com)
  • The PPAR receptor binds selectively with specific receptors in one's bones, muscles, and adipose tissue without inducing hormonal imbalance or other organ damage. (theislandnow.com)
  • Growth hormone deficiency with advanced bone age: phenotypic interaction between GHRH receptor and CYP21A2 mutations diagnosed by sanger and whole exome sequencing. (harvard.edu)
  • The expression of GHRH and its receptors in breast carcinomas with apocrine differentiation-further evidence of the presence of a GHRH pathway in these tumors. (harvard.edu)
  • Sermorelin contains 1st of the 29 amino acids because the GHRH [ Hypothalamic Growth Hormone-Releasing Hormone ] has 44 amino acids. (vanillamist.com)
  • Sermorelin also has the same type of biological activity as the Growth Hormone-Releasing Hormone or GHRH. (vanillamist.com)
  • It can bind the GHRH receptors in the pituitary gland and also stimulate the release and production of the growth hormone greatly. (vanillamist.com)
  • Schematic representation of the interactions between somatostatin (SRIH)-producing neurons in the hypothalamic periventricular nucleus (Pev) and growth hormone releasing hormone (GHRH)-producing neurons in the arcuate nucleus. (endotext.org)
  • R-SRIH and R-GHRH correspond to receptors for the respective peptides. (endotext.org)
  • Sermorelin can mimic growth hormone-releasing hormone, also called GHRH. (visualtasktips.com)
  • When it is administered in the sermorelin form, it will travel through the bloodstream and bind to GHRH receptors present in the pituitary gland. (visualtasktips.com)
  • GHRH, and then there is somatostatin and lastly, ghrelin, which stimulates the release of our growth hormone but by using different receptors. (visualtasktips.com)
  • Longevity in untreated congenital growth hormone deficiency due to a homozygous mutation in the GHRH receptor gene. (cdc.gov)
  • In adult female rodents, acute HPA function following a stressor is markedly greater than it is in males, and this difference has largely been attributed to modulation by the gonadal hormones testosterone and estradiol. (nature.com)
  • The anterior portion of the pituitary gland produces luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the gonads produce estrogen and testosterone. (wikipedia.org)
  • This work has been performed in order to verify whether, in male rats, the decreased secretion of LH and testosterone (T) occurring in old animals is reflected by modifications of luteinizing hormone-releasing hormone (LHRH) receptors at the level of the anterior pituitary and of the testes. (unimi.it)
  • The impaired production of testosterone occurring in aged rats is accompanied by a significant increase of the number of testicular LHRH receptors, indicating that also the intratesticular mechanisms controlling testosterone release undergo significant alterations with aging. (unimi.it)
  • Treatment with degarelix, a novel gonadotrophin-releasing hormone (GnRH) blocker, causes significant reductions in testosterone and prostate-specific antigen (PSA) levels. (ferring.com)
  • In previous studies, other hormones have formula made to reveal Results in not testosterone in satellite cell regulation. (wirelessdesignmag.com)
  • High levels of testosterone in women could result in reduced breast size with other supplements gABA A receptor. (wirelessdesignmag.com)
  • Ghrelin does not get much attention like any other hormones such as insulin, testosterone, growth hormone, and estrogen that it should. (visualtasktips.com)
  • Previous research has linked testosterone, the male sex hormone, to immune system suppression. (vetscite.org)
  • The ovaries produce 25% of circulating testosterone, which is dependent on luteinizing hormone (LH) secreted by the anterior pituitary. (medscape.com)
  • Of the circulating androgens, only testosterone and DHT are able to activate androgen receptors. (medscape.com)
  • 1] In healthy women, 80% of testosterone is bound to sex hormone binding globulin (SHBG), 19% is bound to albumin, and 1% circulates freely in the blood stream. (medscape.com)
  • Androgen receptor gene CAG repeat polymorphism independently influences recovery of male sexual function after testosterone replacement therapy in postsurgical hypogonadotropic hypogonadism. (cdc.gov)
  • The thyroid hormone regulates energy and fat metabolism and protein synthesis by regulating different enzymes that are involved in those processes. (cdc.gov)
  • These hormones help regulate growth and metabolism. (medicalnewstoday.com)
  • It can also mirror the process of a natural growth hormone and how it regulates fat metabolism. (vanillamist.com)
  • Human growth hormone (HGH) is necessary for growth, cell repair, and metabolism. (healthnews.com)
  • This is how the human growth hormone regulates metabolism to support normal growth. (healthnews.com)
  • Carbohydrates are broken down by the body to provide glucose, which is required for effective cell metabolism and growth hormone regulation. (healthnews.com)
  • It was discovered just in 1999 and has profound regulatory effects to influence your metabolism, including your inhibiting stored fat breakdown, increasing or decreasing hunger, and the growth hormone release. (visualtasktips.com)
  • Growth hormone and IGF-I also influence metabolism, including how the body uses and stores carbohydrates, proteins, and fats from food. (medlineplus.gov)
  • Changes in metabolism caused by insensitivity to growth hormone and the resulting shortage of IGF-I cause many of the other features of the condition, including obesity. (medlineplus.gov)
  • The endocrine system-the other communication system in the body-is made up of endocrine glands that produce hormones, chemical substances released into the bloodstream to guide processes such as metabolism, growth, and sexual development. (medscape.com)
  • The thyroid gland secretes thyroxin, a hormone that can reduce concentration and lead to irritability when the thyroid is overactive and cause drowsiness and a sluggish metabolism when the thyroid is underactive. (medscape.com)
  • Growth hormone (GH) is a peptide hormone secreted by the anterior pituitary gland in pulsatile manner, and it has important roles in cell growth and metabolism throughout the body. (medscape.com)
  • Modulation of pancreatic islets-stress axis by hypothalamic releasing hormones and 11beta-hydroxysteroid dehydrogenase. (harvard.edu)
  • The hypothalamic-pituitary-adrenal (HPA) axis, a neuroendocrine network that controls hormonal responses to internal and external challenges in an organism's environment, exhibits strikingly sex-biased activity. (nature.com)
  • These gonadal hormones are produced by the hypothalamic-pituitary-gonadal (HPG) axis and have been shown to determine sex differences in adult HPA function after acute stress via their activational and organizational effects. (nature.com)
  • Moreover, questions remain regarding sex differences in the activity of the HPA axis following chronic stress and the underlying contributions of gonadal hormones and sex chromosomes. (nature.com)
  • The ability of all mammals to cope with any environmental or homeostatic challenge (i.e., stressor), or with perceptual threats to homeostasis, relies upon activation of a neuroendocrine signaling cascade called the hypothalamic-pituitary-adrenal (HPA) axis. (nature.com)
  • We primarily outline what is known about how gonadal hormones and sex chromosomes modulate HPA axis activity following acute stress, and then focus on sex-biased HPA axis activity post-chronic stress, which is far less well understood. (nature.com)
  • The hypothalamic-pituitary-gonadal axis (HPG axis, also known as the hypothalamic-pituitary-ovarian/testicular axis) refers to the hypothalamus, pituitary gland, and gonadal glands as if these individual endocrine glands were a single entity. (wikipedia.org)
  • Fluctuations in this axis cause changes in the hormones produced by each gland and have various local and systemic effects on the body. (wikipedia.org)
  • In oviparous organisms (e.g. fish, reptiles, amphibians, birds), the HPG axis is commonly referred to as the hypothalamus-pituitary-gonadal-liver axis (HPGL-axis) in females. (wikipedia.org)
  • Aging exerts profound influences on the function of the hypothalamic-pituitary-testicular-axis. (unimi.it)
  • Athletes with good muscle mass important nursing considerations potency, mineralocorticoid effects, and duration of hypothalamic-pituitary-adrenal axis suppression. (wirelessdesignmag.com)
  • The purpose of this report is to review the available evidence on the endocrine effects of buprenorphine, particularly as it relates to the hypothalamic-pituitary-gonadal (HPG) axis, which is controversial and not fully defined. (degruyter.com)
  • Based on a comprehensive review of the available literature, we conclude that despite its increasing popularity, buprenorphine has not been adequately studied in respect to its long-term effects on the hypothalamic-pituitary-adrenal (HPA) axis. (degruyter.com)
  • It all relates to something called the hypothalamic-pituitary-adrenal axis. (emofree.com)
  • After infection, activation of the hypothalamic-pituitary-adrenal (HPA) axis leads to the production of glucocorticoids. (nature.com)
  • Strong brain-hormone interaction effects may not be limited to classically known hypothalamic-pituitary-gonadal-axis (HPG-axis) receptor-dense regions. (sciencealert.com)
  • Cyclic fluctuations in HPG-axis hormones exert powerful behavioral, structural, and functional effects through actions on the mammalian central nervous system," Rizor, Babenko, and their team note . (sciencealert.com)
  • Of these isoforms, TR-beta2 is the most important in mediating negative feedback control of the hypothalamic-pituitary-thyroid axis. (nih.gov)
  • This gene encodes a receptor involved in the regulation of the HPA axis - the interaction between the body's hypothalamus, pituitary and adrenal glands. (newindianexpress.com)
  • This axis plays a role in stress response, including production of the body's primary "stress" hormone, cortisol. (newindianexpress.com)
  • Whereas the hypothalamic-pituitary-adrenocortical axis has long been recognized for its involvement in depression, the focus was mostly on cortisol/corticosterone, whereas aldosterone appears to be the 'forgotten' stress hormone. (karger.com)
  • The increase in cortisol may be interpreted as an overactivity of the stress hormone system, i.e. the hypothalamic-pituitary-adrenocortical (HPA) axis, on the basis of a dysfunctional glucocorticoid receptor (GR) feedback. (karger.com)
  • The LL fish also showed an apparently desensitized hypothalamus-pituitary-interrenal HPI axis, with a decrease in pomc and crf expression. (bvsalud.org)
  • Insulin signaling through the insulin receptor increases linear growth through effects on bone and the GH-IGF-1 axis. (medscape.com)
  • Gonadotropin-releasing hormone (GnRH) is secreted from the hypothalamus by GnRH-expressing neurons. (wikipedia.org)
  • In addition, leptin and insulin have stimulatory effects and ghrelin has inhibitory effects on gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus. (wikipedia.org)
  • DACT treatment also decreased release of LH from the pituitary in response to exogenous gonadotropin releasing hormone (GnRH) by 47% compared to control. (cdc.gov)
  • Women receiving donated oocytes were treated with progressively increasing doses of oral estradiol, followed by intravaginal progesterone after previous pituitary desensitization with gonadotropin-releasing hormone agonist. (medscape.com)
  • Cell surface receptors that bind the hypothalamic hormones regulating pituitary cell differentiation, proliferation, and hormone synthesis and release, including the pituitary-releasing and release-inhibiting hormones. (harvard.edu)
  • Examples of peptide hormones include insulin, growth hormone, and thyroid-stimulating hormone. (outlookindia.com)
  • Insulin is a hormone that controls the blood glucose level. (healthnews.com)
  • Studies have shown that nutritional deprivation and malnutrition are associated with abnormal levels of growth hormone and insulin-like growth factors in the body. (healthnews.com)
  • This signaling also leads to the production, primarily by liver cells, of another important growth-promoting hormone called insulin-like growth factor I (IGF-I). (medlineplus.gov)
  • [ 14 ] In addition to its direct effect on the oocytes and/or cumulus cells, GH may also influence oocyte quality indirectly, through activation of insulin-like growth factor-I synthesis or promotion of follicle-stimulating hormone-induced ovarian steroidogenesis (reviewed in [ 15 ] ). (medscape.com)
  • In conclusion, these results suggest that the reduced secretion of LH in old male rats may be linked, at least partially, to a decrease of the number of pituitary LHRH receptors. (unimi.it)
  • Melanocyte-stimulating hormone stimulates prolactin secretion through melanocortin 3-receptors expressed in mammotrophs in themouse pituitary. (elsevierpure.com)
  • Similarly, individual amino acids like lysine, arginine, and glutamine also boost growth hormone secretion in the body. (healthnews.com)
  • Adapted from Epelbaum J: Intrahypothalamic neurohormonal interactions in the control of growth hormone secretion. (endotext.org)
  • Total plasma LH secretion was reduced by 37% compared to control, suggesting that in addition to potential hypothalamic dysfunction, pituitary function is altered. (cdc.gov)
  • Adrenal androgen secretion is dependent on adrenocorticotropic hormone (ACTH) secreted by the anterior pituitary. (medscape.com)
  • Inhibin acts to inhibit activin, which is a peripherally produced hormone that positively stimulates GnRH-producing cells. (wikipedia.org)
  • citation needed] In males, the production of GnRH, LH, and FSH are similar, but the effects of these hormones are different. (wikipedia.org)
  • Degarelix is designed to target and block the GnRH receptor. (ferring.com)
  • Peptide hormones are a group of signaling molecules that are secreted by endocrine glands and regulate various metabolic processes in the body. (outlookindia.com)
  • If extended for a prolonged period, it can aggravate endocrine damage in the hypothalamic-pituitary pathways, leading to permanent gonadal suppression. (theislandnow.com)
  • The anterior pituitary, often called the "master gland," responds to chemical messages from the bloodstream to produce numerous hormones that trigger the action of other endocrine glands. (medscape.com)
  • The endocrine system consists of endocrine glands that produce and secrete hormones into the blood stream to reach and act on target cells of specific organs. (medscape.com)
  • The Endocrine Society has issued a scientific statement regarding hormones and aging and identifies future areas of research. (medscape.com)
  • Some endocrine facts, such as the sequelae coined the term "hormone" for this internal of castration, are deeply rooted in the past. (who.int)
  • In addition, we use biochemical and genetic approaches to identify proteins that interact with the receptor during biosynthesis, signaling and desensitization. (rochester.edu)
  • The action of hormones are transduced by regulating the synthesis of proteins (5% of proteins in the body are regulated by thyroid hormone). (cdc.gov)
  • One of the proteins involved is the melanocortin 1 receptor, or MC1-R, which is located on our pigment-producing cells, the melanocytes. (theamericanmag.com)
  • This work aims to investigate the possible rhythmicity of the different components of the IGF-1 system (igf-1, the igf1ra and igf1rb receptors and the paralogs of its binding proteins IGFBP1 and IGFBP2) in the liver of goldfish. (bvsalud.org)
  • Receptors for dopamine, which is a prolactin release-inhibiting hormone as well as a common neurotransmitter, are not included here. (harvard.edu)
  • The pituitary gland produces thyroid stimulating hormone (TSH) that goes into the blood stream to activate thyroid cells, which then secrete T3 and T4 into the peripheral tissues. (cdc.gov)
  • An overactive thyroid, or hyperthyroidism, means that the gland produces an excess of thyroid hormones and releases them into the bloodstream. (medicalnewstoday.com)
  • The pituitary gland produces the largest number of different hormones and, therefore, has the widest range of effects on the body's functions. (medscape.com)
  • The purpose of this study was to investigate the relationship between the ghrelin or GHSR-1a mRNA levels and clinical characteristics and to confirm the effect of gsp mutations on ghrelin/GHSR-1a system in human GH-secreting pituitary adenomas. (nel.edu)
  • Gsp mutations may upregulate the expression of GHSR-1a mRNA and have no effect on ghrelin mRNA levels in human GH-secreting pituitary adenomas. (nel.edu)
  • GHRP-6 - GHRP-6, a synthetic variant of ghrelin, is a growth hormone secretagogue agonist. (outlookindia.com)
  • The peptide can easily replicate the growth hormone-releasing peptide known as "Ghrelin. (vanillamist.com)
  • If you want to understand it better, then you must know a little about a new hormone called ghrelin. (visualtasktips.com)
  • Ghrelin is also one of the 3 hormones that together act for regulating growth hormone release from your pituitary gland. (visualtasktips.com)
  • Now you have some idea about how ghrelin works and with this understanding of how a peptide mimics ghrelin can initiate the release of your growth hormones must be pretty easy to understand. (visualtasktips.com)
  • The sermorelin ipamorelin blend will bind to ghrelin receptors in your pituitary gland, and switch them in the similar way that ghrelin would do naturally. (visualtasktips.com)
  • The pituitary hormone-regulating hormones are also released by cells other than hypothalamic neurons, and their receptors also occur on non-pituitary cells, especially brain neurons, where their role is less well understood. (harvard.edu)
  • We use a number of model systems (pituitary cells, cell lines, transgenic animals) to study signal pathways for a hypothalamic peptide hormone, TRH, which acts via a G protein coupled receptor to increase cytoplasmic calcium and protein kinase C activity. (rochester.edu)
  • Somatostatin is a hypothalamic hormone, a pancreatic hormone, and a central and peripheral neurotransmitter. (bvsalud.org)
  • The HPA, HPG, and HPT axes are three pathways in which the hypothalamus and pituitary direct neuroendocrine function. (wikipedia.org)
  • Published March 25, 2023 at 440 × 336 in Functional Anatomy of the Hypothalamus and Pituitary . (endotext.org)
  • Most studies report that buprenorphine being a partial agonist/antagonist may not be impacting the pituitary trophic hormones as much. (degruyter.com)
  • This generalized repressing action of REV-ERBα on the expression of hepatic clock genes was confirmed in vitro by using agonists (SR9009 and GSK4112) and antagonist (SR8278) of this receptor. (bvsalud.org)
  • The gsp mutations in 43 cases of human GH-secreting pituitary adenomas were detected using PCR-DNA direct sequencing analysis. (nel.edu)
  • Mutation analysis of inhibitory guanine nucleotide binding protein alpha (GNAI) loci in young and familial pituitary adenomas. (cdc.gov)
  • The posterior pituitary is controlled by the nervous system. (medscape.com)
  • Besides that, this peptide does not come with any side effects, and it has also been shown that it does not release ACTH [Adrenocorticotropic Hormone]. (vanillamist.com)
  • When this peptide accesses our pituitary gland, the pituitary gland in turn will produce another informational substance known as ACTH. (emofree.com)
  • For example, in response to a stressful situation, the pituitary gland may release beta endorphin and ACTH, which, in turn, prompt the suprarenal cortex to release hormones. (medscape.com)
  • Amino acids are the building blocks of protein, and they are excellent sources of nitrogen for hormones. (healthnews.com)
  • Resistance to Thyroid Hormone alpha (RTHα) is characterised by tissue-selective hypothyroidism with near-normal thyroid function tests, and is due to thyroid receptor α gene mutations. (endocrine-abstracts.org)
  • Aryl hydrocarbon receptor activation in lactotropes and gonadotropes interferes with estradiol-dependent and -independent preprolactin, glycoprotein alpha and luteinizing hormone beta gene expression. (umassmed.edu)
  • This gene provides instructions for making a protein called the growth hormone receptor . (medlineplus.gov)
  • Mutations in the GHR gene impair the receptor's ability to bind to growth hormone or to trigger signaling within cells. (medlineplus.gov)
  • Small Indels in the Androgen Receptor Gene: Phenotype Implications and Mechanisms of Mutagenesis. (medscape.com)
  • In females, the positive feedback loop between estrogen and luteinizing hormone help to prepare the follicle in the ovary and the uterus for ovulation and implantation. (wikipedia.org)
  • When the egg is released, the empty follicle sac begins to produce progesterone to inhibit the hypothalamus and the anterior pituitary thus stopping the estrogen-LH positive feedback loop. (wikipedia.org)
  • Pharmacologic therapy for osteoporosis includes most commonly the use of antiresorptive agents to decrease bone resorption, such as bisphosphonates, denosumab, and the selective estrogen-receptor modulator (SERM) raloxifene. (medscape.com)
  • Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol at the receptor level. (theodora.com)
  • Estradiol acts by binding to nuclear receptors that are expressed in estrogen-responsive tissues. (centerwatch.com)
  • The microstructure of white matter - the fatty network of neuronal fibers that transfer information between regions of gray matter - has been found to change with hormonal shifts, including puberty, oral contraception use, gender-affirming hormone therapy, and post-menopausal estrogen therapy. (sciencealert.com)
  • Evidence that atrazine and diaminochlorotriazine inhibit the estrogen/progesterone induced surge of luteinizing hormone in female Sprague-Dawley rats without changing estrogen receptor action. (cdc.gov)
  • High oral doses of atrazine (ATRA) disrupt normal neuroendocrine function, resulting in suppression of the luteinizing hormone (LH) surge in adult, ovariectomized (OVX) estrogen-primed female rats. (cdc.gov)
  • The present study was conducted to investigate the effects of ATRA and DACT on the estradiol benzoate (EB)/progesterone (P) induced LH surge and to determine if such changes correlate with impaired estrogen receptor (ER) function. (cdc.gov)
  • In contrast, ATRA, administered to female rats under dosing conditions which suppressed the LH surge, neither changed the levels of unoccupied ER nor altered the estrogen induced up-regulation of progesterone receptor mRNA. (cdc.gov)
  • Thyroid hormones regulate the way the body uses energy, and they can affect every organ in the body. (medicalnewstoday.com)
  • These hormones regulate the body's growth, and are involved in cell to cell communication, control metabolic activity, sleep-wake homeostasis, and altered regulation or dysregulation of adaptive response in various physiologic and pathophysiologic states. (medscape.com)
  • It is now well known that the anterior pituitary gland of many species including man, synthesise and secrete FSH in multiple heterogeneous forms. (ucl.ac.uk)
  • Meanwhile, the autonomic nervous system stimulates the suprarenal medulla to secrete hormones such as epinephrine into the bloodstream. (medscape.com)
  • Progestins such as norethindrone act by binding to nuclear receptors that are expressed in progesterone responsive tissues. (centerwatch.com)
  • When T4 is converted to T3 it produces the more active thyroid hormone and activates the pathway. (cdc.gov)
  • It does so by binding it with the GHRP receptors and then activates the GH release. (vanillamist.com)
  • This initial stimulation of the receptors stimulate hormone-dependent tumour growth rather than inhibit it, and may lead to a worsening of cancer symptoms or flare. (ferring.com)
  • The study compared the effectiveness and safety of three different dosing regimens of degarelix in 129 men with early and late-stage prostate cancer, who had an initial median PSA level of 61 ng/ml and were recommended as candidates for androgen (male hormone) deprivation therapy. (ferring.com)
  • SARMs (Selective Androgen Receptor Modulators) are new performance-enhancing supplements that are as effective as anabolic steroids, without adverse side effects. (theislandnow.com)
  • A 21-day study on 70 healthy men reviewed the safety and efficacy of the selective androgen receptor modulator, Ligandrol. (theislandnow.com)
  • Their absence or the absence of androgen receptors results in a female phenotype, despite the presence of a 46 XY karyotype (eg, androgen insensitivity syndrome). (medscape.com)
  • Unlike degarelix, these therapies stimulate the natural hormone's receptor on the pituitary gland. (ferring.com)
  • G-protein modulation is considered to participate in the antidepressant mode of action by neurotransmitter G-protein coupled receptors (GPCR). (nel.edu)
  • In this investigation, monoclonal antibodies to follicle stimulating hormone were carefully selected and produced in quantity. (ucl.ac.uk)
  • Their availability has allowed the development of a sensitive, non-competitive, sandwich type radioimmunoassay for human follicle stimulating hormone (hFSH). (ucl.ac.uk)
  • Follicle-stimulating hormone , which rises before ovulation, and helps stimulate the ovary follicles, was associated with thicker gray matter. (sciencealert.com)
  • To this purpose, the affinity constant (Ka) and the maximal binding capacity (Bmax) for the LHRH analog [D-Ser(tBu)6]des-Gly10-LHRH-N-ethylamide were evaluated, by means of a receptor binding assay, in membrane preparations derived from the anterior pituitary and testicular Leydig cells of male rats of 3 and 19 months of age. (unimi.it)
  • Recombinant A2/B5 heterodimeric glycoproteins, purified using cation exchange and size fractionation chromatography, activated human TSH receptors, but not LH and FSH receptors, and showed high affinity to TSH receptors in a radioligand receptor assay. (jci.org)
  • Using an in vitro receptor binding assay, ATRA, but not DACT, inhibited binding of [(3)H]-estradiol to ER. (cdc.gov)
  • Although these actions of gonadal hormones are well supported, the possibility that sex chromosomes similarly influence HPA activity is unexplored. (nature.com)
  • Here we found that the regulation of natural killer (NK) cell function by the glucocorticoid receptor (GR) was required for host survival after infection with mouse cytomegalovirus (MCMV). (nature.com)
  • In a person with hyperthyroidism, the gland makes too much thyroid hormone and releases it into the bloodstream. (medicalnewstoday.com)
  • It is produced by the pituitary gland and released into the bloodstream. (healthnews.com)
  • Mutations in THRA, a ligand-inducible transcription factor, cause Resistance to Thyroid Hormone α (RTHα). (endocrine-abstracts.org)
  • 230) different mutations in thyroid hormone receptor β (TRβ) causing Resistance to Thyroid Hormone β (RTHβ), localise to three clusters within its hormone binding domain. (endocrine-abstracts.org)
  • Background: Resistance to thyroid hormone (TH) beta (RTHβ), caused by mutations in THRB, is characterized by elevated serum (F)T4 accompanied by non-suppressed TSH concentrations. (endocrine-abstracts.org)
  • The release of HGH from the pituitary gland is controlled by two other hormones, growth hormone-releasing hormone and somatostatin. (healthnews.com)
  • Somatostatin on the other hand stops the release of the growth hormone. (healthnews.com)
  • Growth hormone-releasing hormone antagonists abolish the transactivation of human epidermal growth factor receptors in advanced prostate cancer models. (harvard.edu)
  • Inhibitory effects of antagonists of growth hormone-releasing hormone on growth and invasiveness of PC3 human prostate cancer. (harvard.edu)
  • Properties and functions of ubiquitous adenosine receptor were described with number of agonists and antagonists. (nel.edu)
  • An excess of thyroid hormones in the blood may cause the body's functions to speed up. (medicalnewstoday.com)
  • siRNA screen identifies the phosphatase acting on the G protein-coupled thyrotropin-releasing hormone receptor. (rochester.edu)
  • Paroxetine is a direct inhibitor of g protein-coupled receptor kinase 2 and increases myocardial contractility. (rochester.edu)
  • Effect of fluoxetine and adenosine receptor NECA agonist on G alpha q/11 protein of C6 glioma cells. (nel.edu)
  • Abolishing both fluoxetine evoked G alpha q/11 and and 1,4,5 IP3 signalling can indicate parallel interference between G-protein coupled receptors (GPCR) and the cell response. (nel.edu)
  • Kovárů H, Kováru F, Lisá V. Effect of fluoxetine and adenosine receptor NECA agonist on G alpha q/11 protein of C6 glioma cells. (nel.edu)
  • Elevation of growth hormone secretagogue receptor type 1a mRNA expression in human growth hormone-secreting pituitary adenoma harboring G protein alpha subunit mutation. (nel.edu)
  • Xu T, Ye F, Wang B, Tian C, Wang S, Shu K, Guo D, Lei T. Elevation of growth hormone secretagogue receptor type 1a mRNA expression in human growth hormone-secreting pituitary adenoma harboring G protein alpha subunit mutation. (nel.edu)
  • Genetic analyses of bone morphogenetic protein 2, 4 and 7 in congenital combined pituitary hormone deficiency. (cdc.gov)
  • In 1902, Balysis and Startling extracted and identified the first hormone secretin (secreted by cells in the intestinal mucosa), and, in 1927, McGee isolated and purified substances that were androgenic in small amounts (microgram levels). (medscape.com)
  • Thus, 1690, that an organ such as the thyroid secretin was the first hormone to be isolat- pours into the blood substances of physio- ed. (who.int)
  • Certain rare tumors of the pancreas and lungs also can produce hormones that stimulate the pituitary to produce excessive amounts of growth hormone, with similar consequences. (msdmanuals.com)
  • LUMO ), a clinical-stage biopharmaceutical company focused on rare disorders, hosted two key opinion leaders (KOLs) in the field of pediatric endocrinology on December 6th to review the Company's interim data from two Phase 2 trials evaluating oral LUM-201 in moderate idiopathic Pediatric Growth Hormone Deficiency (iPGHD). (streetinsider.com)
  • Presented data are first findings about adenosine receptor interaction with fluoxetine signalling. (nel.edu)
  • Psychological sex differences are thought by some to reflect the interaction of genes , hormones , and social learning on brain development throughout the lifespan. (wikipedia.org)
  • Growth hormone stimulates the growth of bones, muscles, and many internal organs. (msdmanuals.com)
  • In particular, just before ovulation, when the hormones 17β-estradiol and luteinizing hormone rise, the brains of the participants showed white matter changes suggesting faster information transfer. (sciencealert.com)
  • However, the pleiotropic effects of these steroid hormones make it difficult to delineate their precise role(s) in vivo. (nature.com)
  • The "Fragment 176-191 is a growth hormone, which is a modified version of the HGH [ Human Growth Hormone ] molecule. (vanillamist.com)
  • Many of the physical changes are due to the release of human growth hormone (HGH) in the body. (healthnews.com)
  • Human growth hormone is a key hormone during puberty. (healthnews.com)
  • Exercise, sleep, and a balanced diet can all support the release of human growth hormone. (healthnews.com)
  • The growth hormone-releasing hormone, as its name implies, prompts the production and release of the human growth hormone. (healthnews.com)
  • How does the human growth hormone work and how to boost it naturally? (healthnews.com)
  • For normal growth and development, the human growth hormone must be within normal levels in the body. (healthnews.com)
  • Then gradually stop many such created by pituitary organ and later discharged in the circulation system is what human growth hormone. (wirelessdesignmag.com)
  • Effects of aging on pituitary and testicular luteinizing hormone-releasing hormone receptors in the rat / P. Limonta, D. Dondi, R. Maggi, L. Martini, F. Piva. (unimi.it)
  • A lactogenic hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). (umassmed.edu)
  • Disease features arise from variable resistance to TH action in tissues expressing Thyroid Hormone Receptor (TR) β (hypothalamus, pituitary, liver) and from thyrotoxic effects in tissues expressing TRα (heart, bone, brain). (endocrine-abstracts.org)
  • DHT acts by activating the adrenergic receptors in the bone, liver, muscle, and brain tissues. (theislandnow.com)
  • Linkage and comparative mapping studies indicate that the transferred chromosome segment contains a number of candidate genes for hypertension, including genes encoding a brain dopamine receptor and a renal epithelial potassium channel. (jci.org)
  • With the advent of techniques for producing monoclonal antibodies, an additional principle could be added: production and selection of two or more antibodies directed against spatially distant sites on a single hormone or analyte. (ucl.ac.uk)
  • Peroxisome proliferator activated receptor gamma (PPARγ), a ligand-inducible transcription factor, is essential for adipocyte differentiation and lipogenesis. (endocrine-abstracts.org)
  • Further analysis of TR knockout animals revealed, however, that they exhibited a much milder overall phenotype than hypothyroid animals, indicating that receptor loss was not equivalent to ligand loss in vivo. (nih.gov)