The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.
Degradation of CORPUS LUTEUM. In the absence of pregnancy and diminishing trophic hormones, the corpus luteum undergoes luteolysis which is characterized by the involution and cessation of its endocrine function.
Process of maintaining the functions of CORPORA LUTEA, specifically PROGESTERONE production which is regulated primarily by pituitary LUTEINIZING HORMONE in cycling females, and by PLACENTAL HORMONES in pregnant females. The ability to maintain luteal functions is important in PREGNANCY MAINTENANCE.
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.
Corpus luteum hormones are steroid hormones, specifically progesterone and small amounts of estrogen, produced and secreted by the corpus luteum, a temporary endocrine structure formed in the ovary after ovulation during the menstrual cycle.
PROGESTERONE-producing cells in the CORPUS LUTEUM. The large luteal cells derive from the GRANULOSA CELLS. The small luteal cells derive from the THECA CELLS.
The period in the MENSTRUAL CYCLE that follows OVULATION, characterized by the development of CORPUS LUTEUM, increase in PROGESTERONE production by the OVARY and secretion by the glandular epithelium of the ENDOMETRIUM. The luteal phase begins with ovulation and ends with the onset of MENSTRUATION.
Broad plate of dense myelinated fibers that reciprocally interconnect regions of the cortex in all lobes with corresponding regions of the opposite hemisphere. The corpus callosum is located deep in the longitudinal fissure.
A naturally occurring prostaglandin that has oxytocic, luteolytic, and abortifacient activities. Due to its vasocontractile properties, the compound has a variety of other biological actions.
An acyclic state that resembles PREGNANCY in that there is no ovarian cycle, ESTROUS CYCLE, or MENSTRUAL CYCLE. Unlike pregnancy, there is no EMBRYO IMPLANTATION. Pseudopregnancy can be experimentally induced to form DECIDUOMA in the UTERUS.
The period in the ESTROUS CYCLE associated with maximum sexual receptivity and fertility in non-primate female mammals.
The period of cyclic physiological and behavior changes in non-primate female mammals that exhibit ESTRUS. The estrous cycle generally consists of 4 or 5 distinct periods corresponding to the endocrine status (PROESTRUS; ESTRUS; METESTRUS; DIESTRUS; and ANESTRUS).
Birth defect that results in a partial or complete absence of the CORPUS CALLOSUM. It may be isolated or a part of a syndrome (e.g., AICARDI'S SYNDROME; ACROCALLOSAL SYNDROME; ANDERMANN SYNDROME; and HOLOPROSENCEPHALY). Clinical manifestations include neuromotor skill impairment and INTELLECTUAL DISABILITY of variable severity.
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.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
The process of bearing developing young (EMBRYOS or FETUSES) in utero in non-human mammals, beginning from FERTILIZATION to BIRTH.
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).
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.
An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.
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.
The discharge of an OVUM from a rupturing follicle in the OVARY.
The period from onset of one menstrual bleeding (MENSTRUATION) to the next in an ovulating woman or female primate. The menstrual cycle is regulated by endocrine interactions of the HYPOTHALAMUS; the PITUITARY GLAND; the ovaries; and the genital tract. The menstrual cycle is divided by OVULATION into two phases. Based on the endocrine status of the OVARY, there is a FOLLICULAR PHASE and a LUTEAL PHASE. Based on the response in the ENDOMETRIUM, the menstrual cycle is divided into a proliferative and a secretory phase.
Chemical compounds causing LUTEOLYSIS or degeneration.
A nonapeptide hormone released from the neurohypophysis (PITUITARY GLAND, POSTERIOR). It differs from VASOPRESSIN by two amino acids at residues 3 and 8. Oxytocin acts on SMOOTH MUSCLE CELLS, such as causing UTERINE CONTRACTIONS and MILK EJECTION.
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.
Catalyze the oxidation of 3-hydroxysteroids to 3-ketosteroids.
Supporting cells for the developing female gamete in the OVARY. They are derived from the coelomic epithelial cells of the gonadal ridge. Granulosa cells form a single layer around the OOCYTE in the primordial ovarian follicle and advance to form a multilayered cumulus oophorus surrounding the OVUM in the Graafian follicle. The major functions of granulosa cells include the production of steroids and LH receptors (RECEPTORS, LH).
A family of herbivorous leaping MAMMALS of Australia, New Guinea, and adjacent islands. Members include kangaroos, wallabies, quokkas, and wallaroos.
A water-soluble polypeptide (molecular weight approximately 8,000) extractable from the corpus luteum of pregnancy. It produces relaxation of the pubic symphysis and dilation of the uterine cervix in certain animal species. Its role in the human pregnant female is uncertain. (Dorland, 28th ed)
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.
A phase of the ESTROUS CYCLES that follows METESTRUS. Diestrus is a period of sexual quiescence separating phases of ESTRUS in polyestrous animals.
The flattened stroma cells forming a sheath or theca outside the basal lamina lining the mature OVARIAN FOLLICLE. Thecal interstitial or stromal cells are steroidogenic, and produce primarily ANDROGENS which serve as precusors of ESTROGENS in the GRANULOSA CELLS.
A mitochondrial cytochrome P450 enzyme that catalyzes the side-chain cleavage of C27 cholesterol to C21 pregnenolone in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP11A1 gene, catalyzes the breakage between C20 and C22 which is the initial and rate-limiting step in the biosynthesis of various gonadal and adrenal steroid hormones.
Those protein complexes or molecular sites on the surfaces and cytoplasm of gonadal cells that bind luteinizing or chorionic gonadotropic hormones and thereby cause the gonadal cells to synthesize and secrete sex steroids. The hormone-receptor complex is internalized from the plasma membrane and initiates steroid synthesis.
(9 alpha,11 alpha,13E,15S)-9,11,15-Trihydroxyprost-13-en-1-oic acid (PGF(1 alpha)); (5Z,9 alpha,11,alpha,13E,15S)-9,11,15-trihydroxyprosta-5,13-dien-1-oic acid (PGF(2 alpha)); (5Z,9 alpha,11 alpha,13E,15S,17Z)-9,11,15-trihydroxyprosta-5,13,17-trien-1-oic acid (PGF(3 alpha)). A family of prostaglandins that includes three of the six naturally occurring prostaglandins. All naturally occurring PGF have an alpha configuration at the 9-carbon position. They stimulate uterine and bronchial smooth muscle and are often used as oxytocics.
An infraclass of MAMMALS, also called Metatheria, where the young are born at an early stage of development and continue to develop in a pouch (marsupium). In contrast to Eutheria (placentals), marsupials have an incomplete PLACENTA.
A synthetic prostaglandin F2alpha analog. The compound has luteolytic effects and is used for the synchronization of estrus in cattle.
Formation of CORPUS LUTEUM. This process includes capillary invasion of the ruptured OVARIAN FOLLICLE, hypertrophy of the GRANULOSA CELLS and the THECA CELLS, and the production of PROGESTERONE. Luteinization is regulated by LUTEINIZING HORMONE.
The hollow thick-walled muscular organ in the female PELVIS. It consists of the fundus (the body) which is the site of EMBRYO IMPLANTATION and FETAL DEVELOPMENT. Beyond the isthmus at the perineal end of fundus, is CERVIX UTERI (the neck) opening into VAGINA. Beyond the isthmi at the upper abdominal end of fundus, are the FALLOPIAN TUBES.
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 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.
Delay in the attachment and implantation of BLASTOCYST to the uterine ENDOMETRIUM. The blastocyst remains unattached beyond the normal duration thus delaying embryonic development.
Paired or fused ganglion-like bodies in the head of insects. The bodies secrete hormones important in the regulation of metamorphosis and the development of some adult tissues.
A biologically active 20-alpha-reduced metabolite of PROGESTERONE. It is converted from progesterone to 20-alpha-hydroxypregn-4-en-3-one by the 20-ALPHA-HYDROXYSTEROID DEHYDROGENASE in the CORPUS LUTEUM and the PLACENTA.
Cell surface receptors that bind prostaglandins with high affinity and trigger intracellular changes which influence the behavior of cells. Prostaglandin receptor subtypes have been tentatively named according to their relative affinities for the endogenous prostaglandins. They include those which prefer prostaglandin D2 (DP receptors), prostaglandin E2 (EP1, EP2, and EP3 receptors), prostaglandin F2-alpha (FP receptors), and prostacyclin (IP receptors).
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Occurrence or induction of ESTRUS in all of the females in a group at the same time, applies only to non-primate mammals with ESTROUS CYCLE.
The period of the MENSTRUAL CYCLE representing follicular growth, increase in ovarian estrogen (ESTROGENS) production, and epithelial proliferation of the ENDOMETRIUM. Follicular phase begins with the onset of MENSTRUATION and ends with OVULATION.
The periodic shedding of the ENDOMETRIUM and associated menstrual bleeding in the MENSTRUAL CYCLE of humans and primates. Menstruation is due to the decline in circulating PROGESTERONE, and occurs at the late LUTEAL PHASE when LUTEOLYSIS of the CORPUS LUTEUM takes place.
In females, the period that is shortly after giving birth (PARTURITION).
A genus of the subfamily CALLITRICHINAE occurring in forests of Brazil and Bolivia and containing seventeen species.
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.
Physiological mechanisms that sustain the state of PREGNANCY.
Animals produced by the mating of progeny over multiple generations. The resultant strain of animals is virtually identical genotypically. Highly inbred animal lines allow the study of certain traits in a relatively pure form. (Segen, Dictionary of Modern Medicine, 1992)
The external reproductive organ of males. It is composed of a mass of erectile tissue enclosed in three cylindrical fibrous compartments. Two of the three compartments, the corpus cavernosa, are placed side-by-side along the upper part of the organ. The third compartment below, the corpus spongiosum, houses the urethra.
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.
A species of macaque monkey that mainly inhabits the forest of southern India. They are also called bonnet macaques or bonnet monkeys.
Cell surface proteins that bind oxytocin with high affinity and trigger intracellular changes which influence the behavior of cells. Oxytocin receptors in the uterus and the mammary glands mediate the hormone's stimulation of contraction and milk ejection. The presence of oxytocin and oxytocin receptors in neurons of the brain probably reflects an additional role as a neurotransmitter.
Endometrial implantation of EMBRYO, MAMMALIAN at the BLASTOCYST stage.
An enzyme that catalyzes the desaturation (aromatization) of the ring A of C19 androgens and converts them to C18 estrogens. In this process, the 19-methyl is removed. This enzyme is membrane-bound, located in the endoplasmic reticulum of estrogen-producing cells of ovaries, placenta, testes, adipose, and brain tissues. Aromatase is encoded by the CYP19 gene, and functions in complex with NADPH-FERRIHEMOPROTEIN REDUCTASE in the cytochrome P-450 system.
A group of polycyclic compounds closely related biochemically to TERPENES. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (STEROLS), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Steroids containing the fundamental tetracyclic unit with no methyl groups at C-10 and C-13 and with no side chain at C-17. The concept includes both saturated and unsaturated derivatives.
The suborder of aquatic CARNIVORA comprising the WALRUSES; FUR SEALS; SEA LIONS; and EARLESS SEALS. They have fusiform bodies with very short tails and are found on all sea coasts. The offspring are born on land.
A potentially life-threatening condition in which EMBRYO IMPLANTATION occurs outside the cavity of the UTERUS. Most ectopic pregnancies (>96%) occur in the FALLOPIAN TUBES, known as TUBAL PREGNANCY. They can be in other locations, such as UTERINE CERVIX; OVARY; and abdominal cavity (PREGNANCY, ABDOMINAL).
Steroidal compounds related to PROGESTERONE, the major mammalian progestational hormone. Progesterone congeners include important progesterone precursors in the biosynthetic pathways, metabolites, derivatives, and synthetic steroids with progestational activities.
Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.
Excision of the uterus.
Cyst due to the occlusion of the duct of a follicle or small gland.
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.
Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)
Unsaturated pregnane derivatives containing two keto groups on side chains or ring structures.
Artificial introduction of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.
Metabolites or derivatives of PROGESTERONE with hydroxyl group substitution at various sites.
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 group of enzymes that catalyze the reversible reduction-oxidation reaction of 20-hydroxysteroids, such as from a 20-ketosteroid to a 20-alpha-hydroxysteroid (EC 1.1.1.149) or to a 20-beta-hydroxysteroid (EC 1.1.1.53).
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.
An enzymes that catalyzes the reversible reduction-oxidation reaction of 20-alpha-hydroxysteroids, such as from PROGESTERONE to 20-ALPHA-DIHYDROPROGESTERONE.
Occurrence or induction of release of more ova than are normally released at the same time in a given species. The term applies to both animals and humans.
Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.
The fluid surrounding the OVUM and GRANULOSA CELLS in the Graafian follicle (OVARIAN FOLLICLE). The follicular fluid contains sex steroids, glycoprotein hormones, plasma proteins, mucopolysaccharides, and enzymes.
Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.
The mucous membrane lining of the uterine cavity that is hormonally responsive during the MENSTRUAL CYCLE and PREGNANCY. The endometrium undergoes cyclic changes that characterize MENSTRUATION. After successful FERTILIZATION, it serves to sustain the developing embryo.
Analogs or derivatives of prostaglandins F that do not occur naturally in the body. They do not include the product of the chemical synthesis of hormonal PGF.
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.
Elements of limited time intervals, contributing to particular results or situations.
A semisynthetic ergotamine alkaloid that is a dopamine D2 agonist. It suppresses prolactin secretion.
Carrier proteins for OXYTOCIN and VASOPRESSIN. They are polypeptides of about 10-kDa, synthesized in the HYPOTHALAMUS. Neurophysin I is associated with oxytocin and neurophysin II is associated with vasopressin in their respective precursors and during transportation down the axons to the neurohypophysis (PITUITARY GLAND, POSTERIOR).
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.
A phase of the ESTROUS CYCLE that precedes ESTRUS. During proestrus, the Graafian follicles undergo maturation.
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 highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).
Ruminants of the family Bovidae consisting of Bubalus arnee and Syncerus caffer. This concept is differentiated from BISON, which refers to Bison bison and Bison bonasus.
A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.
Proteins produced by organs of the mother or the PLACENTA during PREGNANCY. These proteins may be pregnancy-specific (present only during pregnancy) or pregnancy-associated (present during pregnancy or under other conditions such as hormone therapy or certain malignancies.)
A biologically active 5-alpha-reduced metabolite of plasma PROGESTERONE. It is the immediate precursor of 5-alpha-pregnan-3-alpha-ol-20-one (ALLOPREGNANOLONE), a neuroactive steroid that binds with GABA(A) RECEPTOR.
The period following ESTRUS during which the phenomena of estrus subside in those animals in which pregnancy or pseudopregnancy does not occur.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Compounds that interact with PROGESTERONE RECEPTORS in target tissues to bring about the effects similar to those of PROGESTERONE. Primary actions of progestins, including natural and synthetic steroids, are on the UTERUS and the MAMMARY GLAND in preparation for and in maintenance of PREGNANCY.
Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
The repetitive uterine contraction during childbirth which is associated with the progressive dilation of the uterine cervix (CERVIX UTERI). Successful labor results in the expulsion of the FETUS and PLACENTA. Obstetric labor can be spontaneous or induced (LABOR, INDUCED).
Chemical substances that interrupt pregnancy after implantation.
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.
A potent synthetic analog of GONADOTROPIN-RELEASING HORMONE with D-serine substitution at residue 6, glycine10 deletion, and other modifications.
A metabolite of PROGESTERONE with a hydroxyl group at the 17-alpha position. It serves as an intermediate in the biosynthesis of HYDROCORTISONE and GONADAL STEROID HORMONES.
A delta-4 C19 steroid that is produced not only in the TESTIS, but also in the OVARY and the ADRENAL CORTEX. Depending on the tissue type, androstenedione can serve as a precursor to TESTOSTERONE as well as ESTRONE and ESTRADIOL.
General term for CYSTS and cystic diseases of the OVARY.
An enzyme that catalyzes the reduction of a 3 beta-hydroxy-delta(5)-steroid to 3-oxo-delta(4)-steroid in the presence of NAD. It converts pregnenolone to progesterone and dehydroepiandrosterone to androstenedione. EC 1.1.1.145.
Method to determine the occurrence of OVULATION by direct or indirect means. Indirect methods examine the effects of PROGESTERONE on cervical mucus (CERVIX MUCUS), or basal body temperature. Direct ovulation detection, generally used in fertility treatment, involves analyses of circulating hormones in blood and ULTRASONOGRAPHY.
A state of sexual inactivity in female animals exhibiting no ESTROUS CYCLE. Causes of anestrus include pregnancy, presence of offspring, season, stress, and pathology.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
A group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase pathway. They are extremely potent mediators of a diverse group of physiological processes.
The state of the PENIS when the erectile tissue becomes filled or swollen (tumid) with BLOOD and causes the penis to become rigid and elevated. It is a complex process involving CENTRAL NERVOUS SYSTEM; PERIPHERAL NERVOUS SYSTEMS; HORMONES; SMOOTH MUSCLES; and vascular functions.

Luteal regression in the normally cycling rat: apoptosis, monocyte chemoattractant protein-1, and inflammatory cell involvement. (1/1885)

In hypophysectomized rats, prolactin induces regression of the corpora lutea. Luteal regression is accompanied by infiltration of monocytes/macrophages, declines in luteal mass and plasma progestins, and increased staining for monocyte chemoattractant protein-1 (MCP-1). We investigated whether similar events are induced during the estrous cycle, after the proestrous prolactin surge. Rats were killed on proestrus or on estrus, and one ovary was frozen for immunohistochemical detection of MCP-1, monocytes/macrophages (ED1-positive), and differentiated macrophages (ED2-positive) and for in situ detection of apoptotic nuclei. Corpora lutea of the current (proestrus) or preceding (estrus) cycle were dissected from the ovaries of additional rats and frozen for the same analyses and for determination of total protein content. In sections of whole ovaries, intensity and distribution of MCP-1 staining were increased in corpora lutea of multiple ages on estrus as compared to proestrus, as were numbers of differentiated macrophages and apoptotic nuclei per high-power field. Sections of isolated corpora lutea showed these increases on estrus, and the number of monocytes/macrophages per high-power field was also significantly increased. Accompanying these inflammatory/immune events, the corpora lutea on estrus showed decreased weight and total protein per corpus luteum, as compared to corpora lutea on proestrus. These changes are consistent with a proposed role for prolactin in the initiation of luteal apoptosis and of a sequence of inflammatory/immune events that accompany regression of the rat corpus luteum during the normal estrous cycle.  (+info)

Prolonged mating in prairie voles (Microtus ochrogaster) increases likelihood of ovulation and embryo number. (2/1885)

Prairie voles are induced ovulators that mate frequently in brief bouts over a period of approximately 24 h. We examined 1) impact of mating duration on ovulation and embryo number, 2) incidence of fertilization, 3) temporal pattern of embryo development, 4) embryo progression through the reproductive tract over time, and 5) embryo development in culture. Mating was videotaped to determine first copulation, and the ovaries were examined and the reproductive tracts flushed at 6, 8, 10, 12, 16, 20, and 24 h and 2, 3, and 4 days after first copulation. The number of mature follicles and fresh corpora lutea and the number and developmental stage of embryos were quantified. One, two-, and four-cell embryos were cultured in Whitten's medium. Mature follicles were present at the earliest time examined (6 h). Thirty-eight percent of females that had been paired for < 12 h after the first copulation ovulated, whereas all females paired >/= 12 h after the first copulation ovulated. Virtually all (> 99%) oocytes recovered from females paired for >/= 12 h after first copulation were fertilized. Pairing time after first copulation and mean copulation-bout duration were significant (p < 0.05) determinants of embryo number. Embryos entered the uterine horns and implanted on Days 3 and 4, respectively, after first copulation (Day 0). Embryos cultured in vitro underwent approximately one cell division per day, a rate similar to that in vivo. We conclude that prairie voles ovulate reliably after pairing for >/= 12 h, although some females showed exceptional sensitivity not predicted by the variables quantified. Prolonged mating for longer than 12 h increased the total embryos produced. This mechanism likely has adaptive significance for increasing offspring number.  (+info)

Expression of oestrogen receptor alpha and beta mRNA in corpus luteum of human subjects. (3/1885)

To investigate the role of oestrogen receptor beta (ERbeta) in the function of human ovarian corpus luteum, the levels of luteal ERalpha and ERbeta mRNA were determined using competitive reverse transcription-polymerase chain reaction-Southern blot analysis. The expression of ERalpha and ERbeta mRNA was detected in all luteal samples analysed. Luteal ERalpha and ERbeta mRNA levels were significantly lower (P<0.01 and P<0.05 respectively) at the late secretory phase than those at the early and mid-secretory phases of the endometrium. The ratio of ERalpha to ERbeta mRNA levels showed no change during the secretory phase of the endometrium. This study demonstrates that ERbeta is co-expressed with ERalpha in human corpus luteum and is likely to play a biological role in the regulation of steroidal action of the corpus luteum with ERalpha.  (+info)

Fas and Fas ligand messenger ribonucleic acid and protein expression in the rat corpus luteum during apoptosis-mediated luteolysis. (4/1885)

Apoptosis has been found to occur during regression of the corpus luteum (CL) in many species. The Fas (APO-1/CD95) receptor, a transmembrane protein that induces apoptosis in the cell when bound to Fas ligand (FasL), may be involved. This study established and quantitated the presence and regulation of Fas receptor and FasL in the rat CL during pregnancy and postpartum. Using immunohistochemistry, FasL was localized in CL during pregnancy and postpartum. Fas was localized at Day 1 of pregnancy and at the time of luteolysis. Both Fas and FasL mRNA were found to be expressed throughout pregnancy and postpartum using reverse transcription-polymerase chain reaction (RT-PCR). Relative quantitative RT-PCR established that expression of FasL mRNA increased significantly at Day 22 of pregnancy and decreased by Day 3 postpartum. Spontaneous apoptosis of rat CL placed in an in vitro culture model with serum-free medium was examined by analysis of extracted DNA using 3' end-labeling. Treatment with an anti-rat Fas monoclonal antibody demonstrated a reduction in the occurrence of spontaneous apoptosis. These data support a role for Fas receptor and FasL in rat CL apoptosis during luteolysis.  (+info)

A quantitative study of changes in the human corpus luteum microvasculature during the menstrual cycle. (5/1885)

Endothelial cells are the most abundant cell type in the corpus luteum (CL), and changes in blood vessels have been proposed to play a pivotal role in CL regression. We have studied quantitatively the changes in the human granulosa-luteal microvasculature in CL of various ages: young (Days 17-19 of the cycle), mature (Days 20-24), old (Days 25-27), early regressing (follicular phase of the following cycle), and late regressing (luteal phase of the following cycle). Blood vessels were identified by immunohistochemical staining for the endothelial cell marker CD34. Because of the anisotropy of blood vessels, both vertical and transverse sections of the granulosa-lutein layer (GLL) were used to estimate relative (volume, surface, and length densities) and absolute (mean cross-sectional area) vascular variables. Full luteinization from young to mature CL was accompanied by a 61% increase in the mean cross-sectional area of vascular profiles and a 52% increase in the mean volume of granulosa-lutein cells, as an estimator of changes in the volume of the GLL. In old and early regressing CL, there was a progressive increase in relative structural vascular variables, due to the shrinkage of the GLL, whereas the mean cross-sectional area of capillaries showed a 53% decrease from mature to old CL. Finally, in late regressing CL, there was a decrease in most relative structural variables, in spite of the increasingly shrunken GLL. The decrease in the capillary diameter found at the late luteal phase most likely leads to a decreased blood flow, and early changes in blood vessels could initiate and/or accelerate CL regression.  (+info)

A proposed sequence of hormones controlling the induction of luteal 20alpha-hydroxy steroid dehydrogenase and progesterone withdrawal in the late-pregnant rat. (6/1885)

1. The previously reported induction of luteal 20alpha-hydroxy steroid dehydrogenase by administration of aminoglutethimide to late-pregnant rats was shown to be unaffected by prior removal of the foetuses. Aminoglutethimide therefore does not act via the foetuses in this context. 2. The ability of injected oestrogen to prevent the above induction was lost by delaying the injection for 12h after aminoglutethimide, although the increase in enzyme activity begins only after 24h. 3. Induction of 20alpha-hydroxy steroid dehydrogenase by foetoplacental removal on day 18 of pregnancy was inhibited by human choriogonadotropin, lutropin (luteinizing hormone) and pregnant-mare serum gonadotropin, but not by somatotropin (growth hormone), thyrotropin or follitropin (follicle-stimulating hormone) 4. Indomethacin blocked the normal induction of 20alpha-hydroxy steroid dehydrogenase in late pregnancy and that caused by aminoglutethimide. It partially blocked that caused by human choriogonadotropin given on days 19-20 and that caused by 2-bromo-alpha-ergocryptine on days 5-6, but failed to block that caused by human choriogonadotropin on days 15-16 or by foetoplacental removal on day 18 of pregnancy. 5. These findings, and the control of progesterone synthesis in late pregnancy, are interpreted in terms of a sequence of hormonal or enzymic syntheses, each of which is inhibited by the product of the preceding synthesis.  (+info)

Accumulation of caspase-3 messenger ribonucleic acid and induction of caspase activity in the ovine corpus luteum following prostaglandin F2alpha treatment in vivo. (7/1885)

Caspase-3, a vertebrate homologue of the protein encoded by the Caenorhabditis elegans cell death gene, ced-3, induces apoptosis when overexpressed in eukaryotic cells. Since apoptosis occurs during corpus luteum (CL) regression in many species, including the ewe, these studies were conducted to 1) isolate a cDNA encoding ovine caspase-3, 2) measure steady state amounts of caspase-3 mRNA in the CL during luteolysis induced by prostaglandin F2alpha (PGF2alpha) and during the time of maternal recognition of pregnancy, and 3) measure changes in caspase activity during PGF2alpha-initiated luteal regression. Oligonucleotide primers corresponding to a human caspase-3 cDNA sequence were combined with total RNA from ovine CL in a reverse transcription-polymerase chain reaction-based procedure to amplify a 640-base pair partial cDNA with a nucleotide sequence 86% and 81% identical to the human and rat caspase-3 cDNAs, respectively. CL were collected from ewes at 0, 12, or 24 h after treatment with PGF2alpha on Day 10 of the estrous cycle and from nonpregnant and pregnant ewes on Day 12 or Day 14 of the cycle. Northern blot analysis of total cellular RNA from ovine CL and a radiolabeled ovine caspase-3 cRNA probe indicated the presence of a single mRNA transcript of approximately 2.5 kilobases. Levels of caspase-3 mRNA were approximately 3-fold higher (p < 0.05) in CL at 12 h and 24 h after PGF2alpha in comparison to those levels measured in matched CL from untreated ewes. There were no differences (p > 0.05) in amounts of caspase-3 mRNA in CL on Day 12 or Day 14 of the estrous cycle compared to Day 12 or Day 14 of pregnancy, respectively. Caspase activity in CL (measured by the ability of CL lysates to cleave an artificial caspase substrate) was also significantly (p < 0.05) increased in CL collected after treatment with PGF2alpha compared to CL collected from nontreated ewes. We conclude that physiological cell death during PGF2alpha-induced luteal regression in the ewe is mediated, at least in part, via increased expression and activity of the caspase family of pro-apoptotic proteases.  (+info)

Angiotensin II interacts with prostaglandin F2alpha and endothelin-1 as a local luteolytic factor in the bovine corpus luteum in vitro. (8/1885)

Recent findings suggest that the ovarian renin-angiotensin system may regulate ovarian function through the paracrine/autocrine actions of angiotensin II (Ang II). In this study, we have examined and characterized the local effects of Ang II as a luteolytic factor and its interaction with prostaglandin F2alpha (PGF2alpha) and endothelin-1 (ET-1) in the bovine corpus luteum (CL) of the mid-luteal phase, by using an in vitro microdialysis system (MDS). Ang II was detected in the MDS perfusate (4 pg/ml), and infusion of PGF2alpha (10(-6) M) for 2 h increased the Ang II release by 50-100% during the following experimental period, in addition to its stimulation of ET-1 release. Two 2-h infusions of Ang II (10(-7)-10(-5) M) separated by a 2-h interval induced a dose- and time-dependent decrease of progesterone (P4) release by 41-66%. When the luteal explants were pre-perfused with PGF2alpha (10(-6) M) for 2 h, two consecutive perfusions of Ang II (10(-6) M) at a 2-h interval rapidly reduced the P4 release (by 50%). This reduction occurred 6 h earlier than those of infusions of PGF2alpha or Ang II alone. The simultaneous infusion of either 1) Ang II (10(-6) M) with PGF2alpha (10(-6) M), 2) ET-1 (10(-7) M) with PGF2alpha, or 3) Ang II + ET-1 with PGF2alpha (10(-6) M) for 2 h also induced a rapid and pronounced (60%) decrease in P4 release. Perfusion with the Ang II antagonist blocked the P4-suppressing activity of Ang II alone or PGF2alpha + Ang II infusion. Ang II stimulated the release of ET-1 and oxytocin during infusion but inhibited them after infusion. These results show that Ang II is released in the bovine midcycle CL in vitro, and this peptide, either alone or together with PGF2alpha, can suppress the release of P4. As PGF2alpha directly stimulated Ang II release, Ang II may influence the critical period for starting the cascade of functional luteolysis in vivo and might lead to structural luteolysis with ET-1 as a major vasoconstrictor. The overall results suggest that Ang II may have an important role at luteolysis in the bovine CL.  (+info)

The corpus luteum is a temporary endocrine structure that forms in the ovary after an oocyte (egg) has been released from a follicle during ovulation. It's formed by the remaining cells of the ruptured follicle, which transform into large, hormone-secreting cells.

The primary function of the corpus luteum is to produce progesterone and, to a lesser extent, estrogen during the menstrual cycle or pregnancy. Progesterone plays a crucial role in preparing the uterus for potential implantation of a fertilized egg and maintaining the early stages of pregnancy. If pregnancy does not occur, the corpus luteum will typically degenerate and stop producing hormones after approximately 10-14 days, leading to menstruation.

However, if pregnancy occurs, the developing embryo starts to produce human chorionic gonadotropin (hCG), which signals the corpus luteum to continue secreting progesterone and estrogen until the placenta takes over hormonal production, usually around the end of the first trimester.

Luteolysis is the physiological process that leads to the breakdown and regression of the corpus luteum, a temporary endocrine structure in the ovary that forms after ovulation. The corpus luteum produces progesterone, which supports pregnancy in mammals. If pregnancy does not occur, luteolysis takes place approximately 10-14 days after ovulation in humans and is characterized by the degeneration of the corpus luteum, decreased production of progesterone, and the initiation of the menstrual cycle or the onset of a new reproductive cycle.

The primary event that triggers luteolysis is the release of prostaglandin F2α (PGF2α) from the uterus, which reaches the corpus luteum through the systemic circulation and causes vasoconstriction, reduced blood flow, and structural damage to the corpus luteum. This results in a decline in progesterone levels, which ultimately leads to menstruation or the onset of a new reproductive cycle.

In summary, luteolysis is a crucial process in the female reproductive system that regulates hormonal balance and prepares the body for a new reproductive cycle when pregnancy does not occur.

The Corpus Luteum is a temporary endocrine structure formed in the ovary after the release of a mature egg (ovulation) during the menstrual cycle. It produces progesterone and estrogen, which support the early stages of pregnancy by maintaining the lining of the uterus (endometrium). "Corpus Luteum Maintenance" refers to the physiological processes that sustain the function and survival of the Corpus Luteum.

The maintenance of the Corpus Luteum is primarily regulated by two hormones: luteinizing hormone (LH) and human chorionic gonadotropin (hCG). After ovulation, a surge in LH triggers the formation of the Corpus Luteum. In the absence of pregnancy, the Corpus Luteum begins to degenerate after approximately 10-14 days, leading to a decline in progesterone levels and the onset of menstruation.

However, if conception occurs, the developing embryo starts producing hCG, which shares structural similarities with LH. This hCG maintains the Corpus Luteum by binding to LH receptors and stimulating the continued production of progesterone. The high levels of progesterone help thicken the endometrium and prepare it for implantation of the fertilized egg, ensuring a suitable environment for fetal development during early pregnancy.

In summary, Corpus Luteum Maintenance refers to the hormonal regulation and physiological processes that sustain the function and survival of the Corpus Luteum, primarily through the actions of LH and hCG, leading to the production of progesterone and supporting the early stages of pregnancy.

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.

The corpus luteum is a temporary endocrine structure that forms in the ovary after an oocyte (egg) has been released from a follicle during ovulation. It produces several hormones, including:

1. Progesterone: This hormone prepares the uterus for potential pregnancy by stimulating the growth of blood vessels and glands in the endometrium (lining of the uterus). Progesterone also has an essential role in maintaining pregnancy by preventing menstruation and supporting fetal development.

2. Estradiol: Although primarily produced by developing follicles, the corpus luteum continues to secrete small amounts of estradiol after ovulation. This hormone contributes to the maintenance of the endometrium and helps regulate the menstrual cycle.

3. Relaxin: A peptide hormone that relaxes uterine and pelvic muscles in preparation for childbirth, as well as promoting the growth and remodeling of connective tissues during pregnancy.

4. Inhibin A and B: These are glycoprotein hormones that inhibit the release of follicle-stimulating hormone (FSH) from the pituitary gland, thereby regulating ovarian function and the menstrual cycle.

5. Androstenedione: A weak androgenic steroid hormone that can be converted to testosterone or estradiol in peripheral tissues.

The corpus luteum remains functional for approximately 10-14 days after ovulation if pregnancy does not occur, leading to a decline in hormone production and the onset of menstruation. However, if pregnancy occurs, the developing embryo will produce human chorionic gonadotropin (hCG), which maintains the corpus luteum and its hormonal function until the placenta takes over hormone production around 8-10 weeks of gestation.

Luteal cells, also known as granulosa-lutein cells, are specialized cells found in the ovary that play a crucial role in the menstrual cycle and pregnancy. They are formed from the granulosa cells of the ovarian follicle after ovulation, during which the follicle ruptures and releases the egg (oocyte). The remaining cells then transform into luteal cells, forming a structure called the corpus luteum.

The primary function of luteal cells is to produce and secrete progesterone and estrogen, two hormones that are essential for preparing the uterus for implantation of a fertilized egg and maintaining early pregnancy. Progesterone stimulates the growth of blood vessels in the endometrium (the lining of the uterus), making it thicker and more receptive to the implantation of a fertilized egg. It also suppresses further development of ovarian follicles, preventing the release of additional eggs during pregnancy.

If pregnancy does not occur, the corpus luteum will degenerate, and the levels of progesterone and estrogen will decrease, leading to menstruation. However, if pregnancy occurs, the developing embryo will produce human chorionic gonadotropin (hCG), which stimulates the luteal cells to continue producing progesterone and estrogen until the placenta takes over these functions around the 10th week of gestation.

In summary, luteal cells are specialized ovarian cells that produce and secrete progesterone and estrogen during the menstrual cycle and early pregnancy to prepare the uterus for implantation and maintain pregnancy.

The luteal phase is the second half of the menstrual cycle, starting from ovulation (release of an egg from the ovaries) and lasting until the start of the next menstruation. This phase typically lasts around 12-14 days in a regular 28-day menstrual cycle. During this phase, the remains of the dominant follicle that released the egg transform into the corpus luteum, which produces progesterone and some estrogen to support the implantation of a fertilized egg and maintain the early stages of pregnancy. If pregnancy does not occur, the corpus luteum degenerates, leading to a drop in hormone levels and the start of a new menstrual cycle.

The corpus callosum is the largest collection of white matter in the brain, consisting of approximately 200 million nerve fibers. It is a broad, flat band of tissue that connects the two hemispheres of the brain, allowing them to communicate and coordinate information processing. The corpus callosum plays a crucial role in integrating sensory, motor, and cognitive functions between the two sides of the brain. Damage to the corpus callosum can result in various neurological symptoms, including difficulties with movement, speech, memory, and social behavior.

Dinoprost is a synthetic form of prostaglandin F2α, which is a naturally occurring hormone-like substance in the body. It is used in veterinary medicine as a uterotonic agent to induce labor and abortion in various animals such as cows and pigs. In human medicine, it may be used off-label for similar purposes, but its use must be under the close supervision of a healthcare provider due to potential side effects and risks.

It is important to note that Dinoprost is not approved by the FDA for use in humans, and its availability may vary depending on the country or region. Always consult with a licensed healthcare professional before using any medication, including Dinoprost.

Pseudopregnancy, also known as pseudocyesis or phantom pregnancy, is a psychological condition where an individual (most commonly in women) believes they are pregnant when they are not. This belief is often accompanied by various physical symptoms such as weight gain, abdominal distention, and breast enlargement that mimic those of a genuine pregnancy, despite there being no actual fetal development. These symptoms are caused by the body's hormonal and physiological responses to the individual's strong belief of being pregnant. It is important to note that this condition is rare and can be resolved with proper medical evaluation, counseling, and support.

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.

The estrous cycle is the reproductive cycle in certain mammals, characterized by regular changes in the reproductive tract and behavior, which are regulated by hormonal fluctuations. It is most commonly observed in non-primate mammals such as dogs, cats, cows, pigs, and horses.

The estrous cycle consists of several stages:

1. Proestrus: This stage lasts for a few days and is characterized by the development of follicles in the ovaries and an increase in estrogen levels. During this time, the female may show signs of sexual receptivity, but will not allow mating to occur.
2. Estrus: This is the period of sexual receptivity, during which the female allows mating to take place. It typically lasts for a few days and is marked by a surge in luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which triggers ovulation.
3. Metestrus: This stage follows ovulation and is characterized by the formation of a corpus luteum, a structure that produces progesterone to support pregnancy. If fertilization does not occur, the corpus luteum will eventually regress, leading to the next phase.
4. Diestrus: This is the final stage of the estrous cycle and can last for several weeks or months. During this time, the female's reproductive tract returns to its resting state, and she is not sexually receptive. If pregnancy has occurred, the corpus luteum will continue to produce progesterone until the placenta takes over this function later in pregnancy.

It's important to note that the human menstrual cycle is different from the estrous cycle. While both cycles involve hormonal fluctuations and changes in the reproductive tract, the menstrual cycle includes a shedding of the uterine lining (menstruation) if fertilization does not occur, which is not a feature of the estrous cycle.

Agenesis of the corpus callosum is a birth defect in which the corpus callosum, the part of the brain that connects the two hemispheres and allows them to communicate, fails to develop normally during fetal development. In cases of agenesis of the corpus callosum, the corpus callosum is partially or completely absent.

This condition can vary in severity and may be associated with other brain abnormalities. Some individuals with agenesis of the corpus callosum may have normal intelligence and few symptoms, while others may have intellectual disability, developmental delays, seizures, vision problems, and difficulties with movement and coordination. The exact cause of agenesis of the corpus callosum is not always known, but it can be caused by genetic factors or exposure to certain medications or environmental toxins during pregnancy.

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.

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.

"Animal pregnancy" is not a term that is typically used in medical definitions. However, in biological terms, animal pregnancy refers to the condition where a fertilized egg (or eggs) implants and develops inside the reproductive tract of a female animal, leading to the birth of offspring (live young).

The specific details of animal pregnancy can vary widely between different species, with some animals exhibiting phenomena such as placental development, gestation periods, and hormonal changes that are similar to human pregnancy, while others may have very different reproductive strategies.

It's worth noting that the study of animal pregnancy and reproduction is an important area of biological research, as it can provide insights into fundamental mechanisms of embryonic development, genetics, and evolution.

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.

"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.

An ovarian follicle is a fluid-filled sac in the ovary that contains an immature egg or ovum (oocyte). It's a part of the female reproductive system and plays a crucial role in the process of ovulation.

Ovarian follicles start developing in the ovaries during fetal development, but only a small number of them will mature and release an egg during a woman's reproductive years. The maturation process is stimulated by hormones like follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

There are different types of ovarian follicles, including primordial, primary, secondary, and tertiary or Graafian follicles. The Graafian follicle is the mature follicle that ruptures during ovulation to release the egg into the fallopian tube, where it may be fertilized by sperm.

It's important to note that abnormal growth or development of ovarian follicles can lead to conditions like polycystic ovary syndrome (PCOS) and ovarian cancer.

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.

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.

The menstrual cycle is a series of natural changes that occur in the female reproductive system over an approximate 28-day interval, marking the body's preparation for potential pregnancy. It involves the interplay of hormones that regulate the growth and disintegration of the uterine lining (endometrium) and the release of an egg (ovulation) from the ovaries.

The menstrual cycle can be divided into three main phases:

1. Menstrual phase: The cycle begins with the onset of menstruation, where the thickened uterine lining is shed through the vagina, lasting typically for 3-7 days. This shedding occurs due to a decrease in estrogen and progesterone levels, which are hormones essential for maintaining the endometrium during the previous cycle.

2. Follicular phase: After menstruation, the follicular phase commences with the pituitary gland releasing follicle-stimulating hormone (FSH). FSH stimulates the growth of several ovarian follicles, each containing an immature egg. One dominant follicle usually becomes selected to mature and release an egg during ovulation. Estrogen levels rise as the dominant follicle grows, causing the endometrium to thicken in preparation for a potential pregnancy.

3. Luteal phase: Following ovulation, the ruptured follicle transforms into the corpus luteum, which produces progesterone and estrogen to further support the endometrial thickening. If fertilization does not occur within approximately 24 hours after ovulation, the corpus luteum will degenerate, leading to a decline in hormone levels. This drop triggers the onset of menstruation, initiating a new menstrual cycle.

Understanding the menstrual cycle is crucial for monitoring reproductive health and planning or preventing pregnancies. Variations in cycle length and symptoms are common among women, but persistent irregularities may indicate underlying medical conditions requiring further evaluation by a healthcare professional.

Luteolytic agents are substances that cause the breakdown or regression of the corpus luteum, a temporary endocrine structure in the ovary that forms after ovulation and produces progesterone during early pregnancy in mammals. These agents work by inhibiting the secretion of prostaglandins, which are necessary for maintaining the integrity of the corpus luteum. By causing the breakdown of the corpus luteum, luteolytic agents can induce menstruation or cause the termination of an early pregnancy. Examples of luteolytic agents include prostaglandin F2alpha (PGF2α) and its analogs, as well as certain dopamine agonists such as cabergoline. These agents are used in various clinical settings, including reproductive medicine and veterinary medicine.

Oxytocin is a hormone that is produced in the hypothalamus and released by the posterior pituitary gland. It plays a crucial role in various physiological processes, including social bonding, childbirth, and breastfeeding. During childbirth, oxytocin stimulates uterine contractions to facilitate labor and delivery. After giving birth, oxytocin continues to be released in large amounts during breastfeeding, promoting milk letdown and contributing to the development of the maternal-infant bond.

In social contexts, oxytocin has been referred to as the "love hormone" or "cuddle hormone," as it is involved in social bonding, trust, and attachment. It can be released during physical touch, such as hugging or cuddling, and may contribute to feelings of warmth and closeness between individuals.

In addition to its roles in childbirth, breastfeeding, and social bonding, oxytocin has been implicated in other physiological functions, including regulating blood pressure, reducing anxiety, and modulating pain perception.

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.

3-Hydroxysteroid dehydrogenases (3-HSDs) are a group of enzymes that play a crucial role in steroid hormone biosynthesis. These enzymes catalyze the conversion of 3-beta-hydroxy steroids to 3-keto steroids, which is an essential step in the production of various steroid hormones, including progesterone, cortisol, aldosterone, and sex hormones such as testosterone and estradiol.

There are several isoforms of 3-HSDs that are expressed in different tissues and have distinct substrate specificities. For instance, 3-HSD type I is primarily found in the ovary and adrenal gland, where it catalyzes the conversion of pregnenolone to progesterone and 17-hydroxyprogesterone to 17-hydroxycortisol. On the other hand, 3-HSD type II is mainly expressed in the testes, adrenal gland, and placenta, where it catalyzes the conversion of dehydroepiandrosterone (DHEA) to androstenedione and androstenedione to testosterone.

Defects in 3-HSDs can lead to various genetic disorders that affect steroid hormone production and metabolism, resulting in a range of clinical manifestations such as adrenal insufficiency, ambiguous genitalia, and sexual development disorders.

Granulosa cells are specialized cells that surround and enclose the developing egg cells (oocytes) in the ovaries. They play a crucial role in the growth, development, and maturation of the follicles (the fluid-filled sacs containing the oocytes) by providing essential nutrients and hormones.

Granulosa cells are responsible for producing estrogen, which supports the development of the endometrium during the menstrual cycle in preparation for a potential pregnancy. They also produce inhibin and activin, two hormones that regulate the function of the pituitary gland and its secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

These cells are critical for female reproductive health and fertility. Abnormalities in granulosa cell function can lead to various reproductive disorders, such as polycystic ovary syndrome (PCOS), premature ovarian failure, and infertility.

Macropodidae is not a medical term, but a taxonomic family in the order Diprotodontia, which includes large marsupials commonly known as kangaroos, wallabies, and tree-kangaroos. These animals are native to Australia and New Guinea. They are characterized by their strong hind legs, large feet adapted for leaping, and a long muscular tail used for balance. Some members of this family, particularly the larger kangaroo species, can pose a risk to humans in certain situations, such as vehicle collisions or aggressive encounters during breeding season. However, they are not typically associated with medical conditions or human health.

Relaxin is a hormone produced by the ovaries and, during pregnancy, also by the placenta and the fetal membranes. Its primary function is to relax the uterus and pelvic joints in preparation for childbirth, hence its name. It does this by softening the connective tissues and increasing their elasticity, which allows them to stretch more easily. Relaxin also plays a role in the cardiovascular system during pregnancy, helping to maintain healthy blood pressure levels.

Additionally, relaxin has been shown to have effects on other parts of the body, such as reducing muscle stiffness and joint pain, increasing flexibility, and potentially even playing a role in bone metabolism. However, more research is needed to fully understand all of its functions and potential therapeutic uses.

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.

Diestrus is a stage in the estrous cycle of animals, which is similar to the menstrual cycle in humans. It follows the phase of estrus (or heat), during which the animal is receptive to mating. Diestrus is the period of relative sexual quiescence and hormonal stability between cycles. In this phase, the corpus luteum in the ovary produces progesterone, preparing the uterus for potential pregnancy. If fertilization does not occur, the corpus luteum will degenerate, leading to a drop in progesterone levels and the onset of the next estrous cycle. The duration of diestrus varies among species.

In humans, this phase is analogous to the luteal phase of the menstrual cycle. However, since humans do not exhibit estrous behavior, the term 'diestrus' is typically not used in human reproductive physiology discussions.

Theca cells are specialized cells that are part of the follicle where the egg matures in the ovary. They are located in the outer layer of the follicle and play an important role in producing hormones necessary for the growth and development of the follicle and the egg within it. Specifically, they produce androgens, such as testosterone, which are then converted into estrogens by another type of cells in the follicle called granulosa cells. These hormones help to thicken the lining of the uterus in preparation for a possible pregnancy. In some cases, theca cells can become overactive and produce too much testosterone, leading to conditions such as polycystic ovary syndrome (PCOS).

The Cholesterol Side-Chain Cleavage Enzyme, also known as Steroidogenic Acute Regulatory (StAR) protein or P450scc, is a complex enzymatic system that plays a crucial role in the production of steroid hormones. It is located in the inner mitochondrial membrane of steroid-producing cells, such as those found in the adrenal glands, gonads, and placenta.

The Cholesterol Side-Chain Cleavage Enzyme is responsible for converting cholesterol into pregnenolone, which is the first step in the biosynthesis of all steroid hormones, including cortisol, aldosterone, sex hormones, and vitamin D. This enzymatic complex consists of two components: a flavoprotein called NADPH-cytochrome P450 oxidoreductase, which provides electrons for the reaction, and a cytochrome P450 protein called CYP11A1, which catalyzes the actual cleavage of the cholesterol side chain.

Defects in the Cholesterol Side-Chain Cleavage Enzyme can lead to various genetic disorders, such as congenital lipoid adrenal hyperplasia (CLAH), a rare autosomal recessive disorder characterized by impaired steroidogenesis and accumulation of cholesteryl esters in the adrenal glands and gonads.

Luteinizing Hormone (LH) receptors are specialized protein structures found on the surface of certain cells in the body. They play a crucial role in the endocrine system by binding to specific hormones, such as Luteinizing Hormone, and triggering a series of intracellular events that ultimately lead to changes in cell function.

In particular, LH receptors are found on the cells of the ovaries and testes. In females, when LH binds to its receptor in the ovary, it stimulates ovulation and the development of the corpus luteum, which produces progesterone. In males, LH (also known as Interstitial Cell-Stimulating Hormone in this context) binding to its receptor on testicular Leydig cells triggers the production of testosterone.

Therefore, LH receptors are essential for reproductive processes and the maintenance of secondary sexual characteristics.

Prostaglandin F (PGF) is a type of prostaglandin, which is a group of lipid compounds that are synthesized in the body from fatty acids and have diverse hormone-like effects. Prostaglandin F is a naturally occurring compound that is produced in various tissues throughout the body, including the uterus, lungs, and kidneys.

There are two major types of prostaglandin F: PGF1α and PGF2α. These compounds play important roles in a variety of physiological processes, including:

* Uterine contraction: Prostaglandin F helps to stimulate uterine contractions during labor and childbirth. It is also involved in the shedding of the uterine lining during menstruation.
* Bronchodilation: In the lungs, prostaglandin F can help to relax bronchial smooth muscle and promote bronchodilation.
* Renal function: Prostaglandin F helps to regulate blood flow and fluid balance in the kidneys.

Prostaglandin F is also used as a medication to induce labor, treat postpartum hemorrhage, and manage some types of glaucoma. It is available in various forms, including injections, tablets, and eye drops.

I'm sorry for any confusion, but "Marsupialia" is not a medical term. It is a taxonomic category in biology, specifically an order that includes mammals known as marsupials. These are mammals that carry their young in a pouch after birth. Examples of marsupials include kangaroos, koalas, and opossums. If you have any medical questions or terms you would like defined, I'd be happy to help!

Cloprostenol is a synthetic prostaglandin analog used primarily in veterinary medicine for the treatment and prevention of various conditions. The main therapeutic uses of Cloprostenol include:

1. Induction of parturition (labor) in cows, helping to synchronize calving in managed herds.
2. Termination of pregnancy in cattle, especially in cases where the fetus is nonviable or the pregnancy poses a risk to the animal's health.
3. Treatment of uterine and oviductal disorders, such as pyometra (infection of the uterus) and salpingitis (inflammation of the oviduct), in cattle and pigs.
4. Prevention of postpartum disorders, like endometritis (inflammation of the lining of the uterus) and mastitis (inflammation of the mammary glands), by promoting uterine involution and improving overall reproductive performance in cattle.
5. Control of estrus (heat) in cattle, as an aid in estrous synchronization programs for artificial insemination.

Cloprostenol is available in various formulations, such as intramuscular or subcutaneous injectable solutions, and is typically administered by a veterinarian or trained personnel. It is important to note that the use of Cloprostenol and other prostaglandin analogs should be carried out under the guidance and supervision of a veterinary professional, as improper usage can lead to adverse effects or complications.

Luteinization is the process in which a structure called the granulosa cell in the ovary transforms into a luteal cell after ovulation, or the release of an egg from the ovary. This transformation is triggered by the LH (luteinizing hormone) surge that occurs just before ovulation.

The luteal cells then begin to produce and secrete progesterone and estrogen, which are important hormones for preparing the uterus for implantation of a fertilized egg and maintaining early pregnancy. If pregnancy does not occur, the corpus luteum (the structure formed by the luteinized granulosa cells) will degenerate and progesterone levels will decrease, leading to menstruation.

Luteinization can also refer to a similar process that occurs in the testes, where Sertoli cells transform into Leydig cells in response to LH stimulation, leading to the production of testosterone.

The uterus, also known as the womb, is a hollow, muscular organ located in the female pelvic cavity, between the bladder and the rectum. It has a thick, middle layer called the myometrium, which is composed of smooth muscle tissue, and an inner lining called the endometrium, which provides a nurturing environment for the fertilized egg to develop into a fetus during pregnancy.

The uterus is where the baby grows and develops until it is ready for birth through the cervix, which is the lower, narrow part of the uterus that opens into the vagina. The uterus plays a critical role in the menstrual cycle as well, by shedding its lining each month if pregnancy does not occur.

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.

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.

Delayed embryo implantation is a medical condition that occurs when the fertilized egg (embryo) does not attach to the uterine lining (endometrium) within the expected time frame, typically within 7-10 days after ovulation. In delayed implantation, the embryo may take longer than usual to implant, which can result in a prolonged menstrual cycle or irregular bleeding.

There are several possible reasons for delayed implantation, including hormonal imbalances, uterine abnormalities, immune system dysfunction, and chromosomal abnormalities in the embryo. In some cases, delayed implantation may be a sign of infertility or recurrent pregnancy loss.

Diagnosis of delayed implantation typically involves monitoring hormone levels and tracking menstrual cycles. Imaging tests such as ultrasound or hysteroscopy may also be used to assess the uterine lining and detect any abnormalities that could be contributing to the delay in implantation.

Treatment for delayed implantation depends on the underlying cause. Hormonal therapies, medications to suppress the immune system, or surgery to correct uterine abnormalities may be recommended in some cases. In vitro fertilization (IVF) with embryo transfer may also be considered as a treatment option for couples experiencing delayed implantation and infertility.

The corpora allata are small endocrine glands found in the head of insects, located near the brain. They are part of the insect endocrine system and produce important hormones that regulate various physiological processes, including growth, development, reproduction, and molting. The most well-known hormone produced by the corpora allata is juvenile hormone (JH), which plays a crucial role in maintaining the larval or nymphal stage of insects and preventing metamorphosis into the adult form. As the insect grows and develops, the production of JH decreases, allowing for the initiation of metamorphosis and the emergence of the adult form.

20-Alpha-Dihydroprogesterone is a weak endogenous progestin, a form of progesterone, naturally occurring in the body. It is a metabolite of progesterone and has only about 1% of the activity of its parent compound. It is formed by the action of the enzyme 5-alpha-reductase on progesterone.

Medical Definition:
20-Alpha-Dihydroprogesterone (20-α-DHP): An endogenous progestin, a weak metabolite of progesterone, formed by the action of 5-alpha-reductase on progesterone. It has only about 1% of the activity of its parent compound, progesterone.

Prostaglandin receptors are a type of cell surface receptor that bind and respond to prostaglandins, which are hormone-like lipid compounds that play important roles in various physiological and pathophysiological processes in the body. Prostaglandins are synthesized from arachidonic acid by the action of enzymes called cyclooxygenases (COX) and are released by many different cell types in response to various stimuli.

There are four major subfamilies of prostaglandin receptors, designated as DP, EP, FP, and IP, each of which binds specifically to one or more prostaglandins with high affinity. These receptors are G protein-coupled receptors (GPCRs), which means that they activate intracellular signaling pathways through the interaction with heterotrimeric G proteins.

The activation of prostaglandin receptors can lead to a variety of cellular responses, including changes in ion channel activity, enzyme activation, and gene expression. These responses can have important consequences for many physiological processes, such as inflammation, pain perception, blood flow regulation, and platelet aggregation.

Prostaglandin receptors are also targets for various drugs used in clinical medicine, including nonsteroidal anti-inflammatory drugs (NSAIDs) and prostaglandin analogs. NSAIDs work by inhibiting the enzymes that synthesize prostaglandins, while prostaglandin analogs are synthetic compounds that mimic the effects of natural prostaglandins by activating specific prostaglandin receptors.

In summary, prostaglandin receptors are a class of cell surface receptors that bind and respond to prostaglandins, which are important signaling molecules involved in various physiological processes. These receptors are targets for various drugs used in clinical medicine and play a critical role in the regulation of many bodily functions.

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.

Estrus synchronization is a veterinary medical procedure used in the management of domestic animals, such as cattle and sheep. It is a process of coordinating the estrous cycles of animals so that they can be bred at the same time or have their fertility treatments performed simultaneously. This is achieved through the use of various hormonal therapies, including progestins, prostaglandins, and gonadotropin-releasing hormones (GnRH).

The goal of estrus synchronization is to improve reproductive efficiency in animal production systems by ensuring that a larger number of animals become pregnant during a shorter breeding season. This can lead to more uniform calf or lamb crops, reduced labor and management costs, and increased profitability for farmers and ranchers.

Estrus synchronization is a complex process that requires careful planning and implementation, as well as ongoing monitoring and evaluation of the animals' reproductive performance. It is typically performed under the guidance of a veterinarian or animal reproduction specialist.

The follicular phase is a term used in reproductive endocrinology, which refers to the first part of the menstrual cycle. This phase begins on the first day of menstruation and lasts until ovulation. During this phase, several follicles in the ovaries begin to mature under the influence of follicle-stimulating hormone (FSH) released by the pituitary gland.

Typically, one follicle becomes dominant and continues to mature, while the others regress. The dominant follicle produces increasing amounts of estrogen, which causes the lining of the uterus to thicken in preparation for a possible pregnancy. The follicular phase can vary in length, but on average it lasts about 14 days.

It's important to note that the length and characteristics of the follicular phase can provide valuable information in diagnosing various reproductive disorders, such as polycystic ovary syndrome (PCOS) or thyroid dysfunction.

Menstruation is the regular, cyclical shedding of the uterine lining (endometrium) in women and female individuals of reproductive age, accompanied by the discharge of blood and other materials from the vagina. It typically occurs every 21 to 35 days and lasts for approximately 2-7 days. This process is a part of the menstrual cycle, which is under the control of hormonal fluctuations involving follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen, and progesterone.

The menstrual cycle can be divided into three main phases:

1. Menstruation phase: The beginning of the cycle is marked by the start of menstrual bleeding, which signals the breakdown and shedding of the endometrium due to the absence of pregnancy and low levels of estrogen and progesterone. This phase typically lasts for 2-7 days.

2. Proliferative phase: After menstruation, under the influence of rising estrogen levels, the endometrium starts to thicken and regenerate. The uterine lining becomes rich in blood vessels and glands, preparing for a potential pregnancy. This phase lasts from day 5 until around day 14 of an average 28-day cycle.

3. Secretory phase: Following ovulation (release of an egg from the ovaries), which usually occurs around day 14, increased levels of progesterone cause further thickening and maturation of the endometrium. The glands in the lining produce nutrients to support a fertilized egg. If pregnancy does not occur, both estrogen and progesterone levels will drop, leading to menstruation and the start of a new cycle.

Understanding menstruation is essential for monitoring reproductive health, identifying potential issues such as irregular periods or menstrual disorders, and planning family planning strategies.

The postpartum period refers to the time frame immediately following childbirth, typically defined as the first 6-12 weeks. During this time, significant physical and emotional changes occur as the body recovers from pregnancy and delivery. Hormone levels fluctuate dramatically, leading to various symptoms such as mood swings, fatigue, and breast engorgement. The reproductive system also undergoes significant changes, with the uterus returning to its pre-pregnancy size and shape, and the cervix closing.

It is essential to monitor physical and emotional health during this period, as complications such as postpartum depression, infection, or difficulty breastfeeding may arise. Regular check-ups with healthcare providers are recommended to ensure a healthy recovery and address any concerns. Additionally, proper rest, nutrition, and support from family and friends can help facilitate a smooth transition into this new phase of life.

Callithrix is a genus of New World monkeys, also known as marmosets. They are small, active primates found in the forests of South and Central America. The term "Callithrix" itself is derived from the Greek words "kallis" meaning beautiful and "thrix" meaning hair, referring to their thick, vibrantly colored fur.

Marmosets in the genus Callithrix are characterized by their slender bodies, long, bushy tails, and specialized dental structures that allow them to gouge tree bark to extract sap and exudates, which form a significant part of their diet. They also consume fruits, insects, and small vertebrates.

Some well-known species in this genus include the common marmoset (Callithrix jacchus), the white-headed marmoset (Callithrix geoffroyi), and the buffy-tufted-ear marmoset (Callithrix aurita). Marmosets are popular subjects of research due to their small size, short gestation period, and ease of breeding in captivity.

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.

Pregnancy maintenance refers to the ongoing process and care required to support and sustain a healthy pregnancy until childbirth. This includes regular prenatal check-ups to monitor the health of both the mother and the developing fetus, proper nutrition, regular exercise, and avoiding harmful behaviors such as smoking or consuming alcohol. In some cases, pregnancy maintenance may also include medical interventions such as hormone treatments or bed rest. The goal of pregnancy maintenance is to ensure the best possible outcome for both the mother and the baby.

Inbreeding in animals refers to the mating of closely related individuals, such as siblings or offspring of siblings, over multiple generations. An inbred strain is a population of animals produced by this repeated mating of close relatives, which results in a high degree of genetic similarity among members of the strain.

Inbreeding can lead to an increase in homozygosity, where identical alleles are present at corresponding loci on both chromosomes. This can result in the expression of recessive traits, some of which may be deleterious or even lethal. However, inbred strains also have advantages, such as reduced genetic variability, which makes them useful for scientific research.

Inbred strains are commonly used in biomedical research, including genetics, immunology, and behavioral studies. They provide a consistent and controlled genetic background, allowing researchers to study the effects of specific genes or environmental factors with greater precision. Additionally, inbred strains can be crossed with other strains to create hybrid populations, which can be used to map quantitative trait loci (QTL) and identify genes associated with complex traits.

The penis is a part of the male reproductive and urinary systems. It has three parts: the root, the body, and the glans. The root attaches to the pelvic bone and the body makes up the majority of the free-hanging portion. The glans is the cone-shaped end that protects the urethra, the tube inside the penis that carries urine from the bladder and semen from the testicles.

The penis has a dual function - it acts as a conduit for both urine and semen. During sexual arousal, the penis becomes erect when blood fills two chambers inside its shaft. This process is facilitated by the relaxation of the smooth muscles in the arterial walls and the trappping of blood in the corpora cavernosa. The stiffness of the penis enables sexual intercourse. After ejaculation, or when the sexual arousal passes, the muscles contract and the blood flows out of the penis back into the body, causing it to become flaccid again.

The foreskin, a layer of skin that covers the glans, is sometimes removed in a procedure called circumcision. Circumcision is often performed for religious or cultural reasons, or as a matter of family custom. In some countries, it's also done for medical reasons, such as to treat conditions like phimosis (an inability to retract the foreskin) or balanitis (inflammation of the glans).

It's important to note that any changes in appearance, size, or function of the penis should be evaluated by a healthcare professional, as they could indicate an underlying medical condition.

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.

"Macaca radiata" is a species of monkey that is native to India. It is often referred to as the "bonnet macaque" due to the distinctive cap of hair on its head. This species is widely studied in the field of primatology and has been an important model organism in biomedical research, particularly in the areas of neuroscience and infectious disease. However, I couldn't find a specific medical definition for "Macaca radiata".

Oxytocin receptors are specialized protein structures found on the surface of cells, primarily in the uterus and mammary glands. They bind to the hormone oxytocin, which is produced in the hypothalamus and released into the bloodstream by the posterior pituitary gland.

When oxytocin binds to its receptor, it triggers a series of intracellular signaling events that lead to various physiological responses. In the uterus, oxytocin receptors play a crucial role in promoting contractions during labor and childbirth. In the mammary glands, they stimulate milk letdown and ejection during breastfeeding.

Oxytocin receptors have also been identified in other tissues, including the brain, heart, and kidneys, where they are involved in a variety of functions such as social bonding, sexual behavior, stress response, and cardiovascular regulation. Dysregulation of oxytocin receptor function has been implicated in several pathological conditions, including anxiety disorders, autism spectrum disorder, and hypertension.

Embryo implantation is the process by which a fertilized egg, or embryo, becomes attached to the wall of the uterus (endometrium) and begins to receive nutrients from the mother's blood supply. This process typically occurs about 6-10 days after fertilization and is a critical step in the establishment of a successful pregnancy.

During implantation, the embryo secretes enzymes that help it to burrow into the endometrium, while the endometrium responds by producing receptors for the embryo's enzymes and increasing blood flow to the area. The embryo then begins to grow and develop, eventually forming the placenta, which will provide nutrients and oxygen to the developing fetus throughout pregnancy.

Implantation is a complex process that requires precise timing and coordination between the embryo and the mother's body. Factors such as age, hormonal imbalances, and uterine abnormalities can affect implantation and increase the risk of miscarriage or difficulty becoming pregnant.

Aromatase is a enzyme that belongs to the cytochrome P450 superfamily, and it is responsible for converting androgens into estrogens through a process called aromatization. This enzyme plays a crucial role in the steroid hormone biosynthesis pathway, particularly in females where it is primarily expressed in adipose tissue, ovaries, brain, and breast tissue.

Aromatase inhibitors are used as a treatment for estrogen receptor-positive breast cancer in postmenopausal women, as they work by blocking the activity of aromatase and reducing the levels of circulating estrogens in the body.

Steroids, also known as corticosteroids, are a type of hormone that the adrenal gland produces in your body. They have many functions, such as controlling the balance of salt and water in your body and helping to reduce inflammation. Steroids can also be synthetically produced and used as medications to treat a variety of conditions, including allergies, asthma, skin conditions, and autoimmune disorders.

Steroid medications are available in various forms, such as oral pills, injections, creams, and inhalers. They work by mimicking the effects of natural hormones produced by your body, reducing inflammation and suppressing the immune system's response to prevent or reduce symptoms. However, long-term use of steroids can have significant side effects, including weight gain, high blood pressure, osteoporosis, and increased risk of infections.

It is important to note that anabolic steroids are a different class of drugs that are sometimes abused for their muscle-building properties. These steroids are synthetic versions of the male hormone testosterone and can have serious health consequences when taken in large doses or without medical supervision.

"Gonanes" is not a recognized medical term. However, in the field of chemistry and pharmacology, gonanes refer to a class of steroidal compounds that have a chemical structure similar to testosterone, which is the primary male sex hormone. These compounds are often used as the basis for developing drugs that can affect the reproductive system or other systems in the body that are influenced by testosterone and its derivatives.

It's important to note that while gonanes may have implications for medical research and drug development, they do not have a specific medical definition in the same way that terms like "myocardial infarction" or "diabetes mellitus" do.

Pinnipedia is not a medical term, but a taxonomic category in zoology. It refers to a group of marine mammals that include seals, sea lions, walruses, and related extinct species. These animals are characterized by their limbs being modified into flippers, which makes them well-adapted for life in the water. They are often studied in fields such as marine biology and veterinary medicine.

Ectopic pregnancy is a type of abnormal pregnancy that occurs outside the uterine cavity. The most common site for an ectopic pregnancy is the fallopian tube, accounting for about 95% of cases. This condition is also known as tubal pregnancy. Other less common sites include the ovary, cervix, and abdominal cavity.

In a normal pregnancy, the fertilized egg travels down the fallopian tube and implants itself in the lining of the uterus. However, in an ectopic pregnancy, the fertilized egg implants and starts to develop somewhere other than the uterus. The growing embryo cannot survive outside the uterus, and if left untreated, an ectopic pregnancy can cause life-threatening bleeding due to the rupture of the fallopian tube or other organs.

Symptoms of ectopic pregnancy may include abdominal pain, vaginal bleeding, shoulder pain, lightheadedness, fainting, and in severe cases, shock. Diagnosis is usually made through a combination of medical history, physical examination, ultrasound, and blood tests to measure the levels of human chorionic gonadotropin (hCG), a hormone produced during pregnancy.

Treatment for ectopic pregnancy depends on several factors, including the location, size, and growth rate of the ectopic mass, as well as the patient's overall health and desire for future pregnancies. Treatment options may include medication to stop the growth of the embryo or surgery to remove the ectopic tissue. In some cases, both methods may be used together. Early diagnosis and treatment can help prevent serious complications and improve the chances of preserving fertility in future pregnancies.

Progesterone congeners refer to synthetic or naturally occurring compounds that are structurally similar to progesterone, a steroid hormone involved in the menstrual cycle, pregnancy, and embryogenesis. These compounds have similar chemical structures to progesterone and may exhibit similar physiological activities, although they can also have unique properties and uses. Examples of progesterone congeners include various synthetic progestins used in hormonal contraceptives and other medical treatments.

Equine Gonadotropins are glycoprotein hormones derived from the pituitary gland of horses. They consist of two subunits: a common alpha subunit and a unique beta subunit that determines the biological activity of each hormone. There are two main types of equine gonadotropins: Equine Follicle Stimulating Hormone (eFSH) and Equine Luteinizing Hormone (eLH).

eFSH plays a crucial role in the growth and development of ovarian follicles in females, while eLH stimulates ovulation and the production of sex steroids in both males and females. These hormones are often used in veterinary medicine to induce ovulation and improve fertility in horses, as well as in research to study the physiology and biochemistry of gonadotropins and reproduction. It's important to note that equine gonadotropins have limited application in human reproductive medicine due to potential immunogenic reactions and other safety concerns.

A hysterectomy is a surgical procedure that involves the removal of the uterus (womb). Depending on the specific medical condition and necessity, a hysterectomy may also include the removal of the ovaries, fallopian tubes, and surrounding tissues. There are different types of hysterectomies, including:

1. Total hysterectomy: The uterus and cervix are removed.
2. Supracervical (or subtotal) hysterectomy: Only the upper part of the uterus is removed, leaving the cervix intact.
3. Radical hysterectomy: This procedure involves removing the uterus, cervix, surrounding tissues, and the upper part of the vagina. It is typically performed in cases of cervical cancer.
4. Oophorectomy: The removal of one or both ovaries can be performed along with a hysterectomy depending on the patient's medical condition and age.
5. Salpingectomy: The removal of one or both fallopian tubes can also be performed along with a hysterectomy if needed.

The reasons for performing a hysterectomy may include but are not limited to: uterine fibroids, heavy menstrual bleeding, endometriosis, adenomyosis, pelvic prolapse, cervical or uterine cancer, and chronic pelvic pain. The choice of the type of hysterectomy depends on the patient's medical condition, age, and personal preferences.

A Follicular Cyst is a type of cyst that forms within a follicle, which is the sac-like structure in the skin that contains and protects a hair root. In particular, it refers to a specific condition in the ovary where a follicle fails to rupture or release an egg after maturation, instead continuing to grow and fill with fluid, forming a cyst. These cysts are usually asymptomatic but can become large and cause symptoms such as pelvic pain or discomfort, irregular menstrual cycles, or abnormal vaginal bleeding. In most cases, follicular cysts resolve on their own within 2-3 menstrual cycles, but in rare cases, they may require medical intervention if they become complicated or do not resolve.

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.

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.

Pregnenediones are a class of steroid hormones that contain a pregnane structure, which is a skeleton formed by four fused cyclohexane rings. Specifically, pregnenediones are characterized by having a ketone group (a carbonyl group, -C=O) at the 20th carbon position of this pregnane structure. They can be further classified into various subgroups based on the presence and location of other functional groups in the molecule.

Pregnenediones are not typically used as medications, but they do play important roles in the human body. For example, progesterone is a naturally occurring pregnenedione that plays a crucial role in maintaining pregnancy and preparing the uterus for childbirth. Other pregnenediones may also have hormonal activity or serve as intermediates in the synthesis of other steroid hormones.

Artificial insemination (AI) is a medical procedure that involves the introduction of sperm into a female's cervix or uterus for the purpose of achieving pregnancy. This procedure can be performed using sperm from a partner or a donor. It is often used when there are issues with male fertility, such as low sperm count or poor sperm motility, or in cases where natural conception is not possible due to various medical reasons.

There are two types of artificial insemination: intracervical insemination (ICI) and intrauterine insemination (IUI). ICI involves placing the sperm directly into the cervix, while IUI involves placing the sperm directly into the uterus using a catheter. The choice of procedure depends on various factors, including the cause of infertility and the preferences of the individuals involved.

Artificial insemination is a relatively simple and low-risk procedure that can be performed in a doctor's office or clinic. It may be combined with fertility drugs to increase the chances of pregnancy. The success rate of artificial insemination varies depending on several factors, including the age and fertility of the individuals involved, the cause of infertility, and the type of procedure used.

Hydroxyprogesterone is a synthetic form of the natural hormone progesterone, which is produced by the body during pregnancy to support the growth and development of the fetus. Hydroxyprogesterone is used in medical treatments to help prevent preterm birth in certain high-risk pregnancies.

There are several different forms of hydroxyprogesterone that have been developed for use as medications, including:

1. Hydroxyprogesterone caproate (HPC): This is a synthetic form of progesterone that is given as an injection once a week to help prevent preterm birth in women who have previously given birth prematurely. It works by helping to thicken the lining of the uterus and prevent contractions.
2. 17-Hydroxyprogesterone: This is a natural hormone that is produced by the body during pregnancy, but it can also be synthesized in a laboratory for use as a medication. It has been studied for its potential to help prevent preterm birth, although it is not currently approved for this use by the U.S. Food and Drug Administration (FDA).
3. 21-Hydroxyprogesterone: This is another natural hormone that is produced by the body during pregnancy, but it can also be synthesized in a laboratory for use as a medication. It has been studied for its potential to help prevent preterm birth and for its ability to reduce the risk of certain complications in women with a history of premature birth.

It's important to note that hydroxyprogesterone should only be used under the supervision of a healthcare provider, as it can have side effects and may not be appropriate for all women. If you are pregnant or planning to become pregnant and have concerns about preterm birth, it's important to discuss your options with your healthcare provider.

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.

20-Hydroxysteroid Dehydrogenases (20-HSDs) are a group of enzymes that play a crucial role in the metabolism of steroid hormones. These enzymes catalyze the conversion of steroid hormone precursors to their active forms by adding or removing a hydroxyl group at the 20th carbon position of the steroid molecule.

There are several isoforms of 20-HSDs, each with distinct tissue distribution and substrate specificity. The most well-known isoforms include 20-HSD type I and II, which have opposing functions in regulating the activity of cortisol, a glucocorticoid hormone produced by the adrenal gland.

Type I 20-HSD, primarily found in the liver and adipose tissue, converts inactive cortisone to its active form, cortisol. In contrast, type II 20-HSD, expressed mainly in the kidney, brain, and immune cells, catalyzes the reverse reaction, converting cortisol back to cortisone.

Dysregulation of 20-HSDs has been implicated in various medical conditions, such as metabolic disorders, inflammatory diseases, and cancers. Therefore, understanding the function and regulation of these enzymes is essential for developing targeted therapies for these conditions.

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.

20-α-Hydroxysteroid Dehydrogenase (20-α-HSD) is an enzyme that catalyzes the conversion of steroids, specifically the oxidation of 20α-hydroxysteroids to 20-keto steroids. This enzyme plays a crucial role in the metabolism and regulation of steroid hormones, such as corticosteroids and progestogens.

In the adrenal gland, 20-α-HSD is involved in the biosynthesis and interconversion of various corticosteroids, including cortisol, cortisone, and aldosterone. By catalyzing the conversion of cortisol to cortisone or vice versa, this enzyme helps maintain a balance between active and inactive forms of these hormones, which is essential for proper physiological functioning.

In the reproductive system, 20-α-HSD is involved in the metabolism of progestogens, such as progesterone and its derivatives. This enzyme can convert active forms of progestogens into their inactive counterparts, thereby regulating their levels and activity within the body.

Dysregulation or mutations in 20-α-HSD have been implicated in several medical conditions, including adrenal insufficiency, congenital adrenal hyperplasia, and certain reproductive disorders.

Superovulation, also known as controlled ovarian stimulation (COS), refers to the process of inducing the development and release of multiple mature ova (eggs) from the ovaries during a single reproductive cycle. This is achieved through the administration of exogenous gonadotropins or other fertility medications, which stimulate the ovarian follicles to grow and mature beyond the normal number. Superovulation is commonly used in assisted reproductive technologies (ART) such as in vitro fertilization (IVF) to increase the chances of successful conception by obtaining a larger number of ova for fertilization and embryo transfer.

Ovulation induction is a medical procedure that involves the stimulation of ovulation (the release of an egg from the ovaries) in women who have difficulties conceiving due to ovulatory disorders. This is typically achieved through the use of medications such as clomiphene citrate or gonadotropins, which promote the development and maturation of follicles in the ovaries containing eggs. The process is closely monitored through regular ultrasounds and hormone tests to ensure appropriate response and minimize the risk of complications like multiple pregnancies. Ovulation induction may be used as a standalone treatment or in conjunction with other assisted reproductive technologies (ART), such as intrauterine insemination (IUI) or in vitro fertilization (IVF).

Follicular fluid is the fluid that accumulates within the follicle (a small sac or cyst) in the ovary where an egg matures. This fluid contains various chemicals, hormones, and proteins that support the growth and development of the egg cell. It also contains metabolic waste products and other substances from the granulosa cells (the cells that surround the egg cell within the follicle). Follicular fluid is often analyzed in fertility treatments and studies as it can provide valuable information about the health and viability of the egg cell.

I'm sorry for any confusion, but "horses" is not a medical term. It is the common name given to the species *Equus ferus caballus*, which are large domesticated mammals used for transportation, work, and recreation. If you have any questions about horses or a related topic that you would like a medical perspective on, please let me know and I'd be happy to help!

The endometrium is the innermost layer of the uterus, which lines the uterine cavity and has a critical role in the menstrual cycle and pregnancy. It is composed of glands and blood vessels that undergo cyclic changes under the influence of hormones, primarily estrogen and progesterone. During the menstrual cycle, the endometrium thickens in preparation for a potential pregnancy. If fertilization does not occur, it will break down and be shed, resulting in menstruation. In contrast, if implantation takes place, the endometrium provides essential nutrients to support the developing embryo and placenta throughout pregnancy.

Prostaglandins F (PGF) are a type of prostaglandin, which are naturally occurring hormone-like substances that have various effects on the body. They are produced in response to injury or infection and play a role in inflammation, fever, and pain. Prostaglandins F are synthesized for medical use and are available as drugs known as dinoprost and cloprostenol.

Dinoprost is a synthetic form of PGF2α (prostaglandin F2 alpha) used to induce labor and treat postpartum hemorrhage. It works by causing the uterus to contract, helping to expel the placenta and reduce bleeding.

Cloprostenol is a synthetic form of PGF2α used in veterinary medicine as a reproductive hormone to synchronize estrus cycles in cattle and sheep, as well as to induce parturition (giving birth) in cows. It works by stimulating the contraction of the uterus and promoting the release of luteinizing hormone (LH), which triggers ovulation.

It is important to note that these synthetic prostaglandins should only be used under the supervision of a healthcare professional or veterinarian, as they can have side effects and interactions with other medications.

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.

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.

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).

Neurophysins are small protein molecules that are derived from the larger precursor protein, pro-neurophysin. They are synthesized in the hypothalamus of the brain and are stored in and released from neurosecretory granules, along with neurohypophysial hormones such as oxytocin and vasopressin.

Neurophysins serve as carrier proteins for these hormones, helping to stabilize them and facilitate their transport and release into the bloodstream. There are two main types of neurophysins, neurophysin I and neurophysin II, which are associated with oxytocin and vasopressin, respectively.

Neurophysins have been studied for their potential role in various physiological processes, including water balance, social behavior, and reproductive functions. However, their precise mechanisms of action and functional significance are still not fully understood.

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.

Proestrus is a stage in the estrous cycle of animals, specifically referring to the phase preceding estrus (heat) during which follicle development and estrogen production occur. It is characterized by the swelling of the vulva and the onset of behaviors indicating readiness to mate, although the animal is not yet receptive to males. This stage typically lasts around 2-13 days, depending on the species. In humans, this equivalent phase does not exist due to menstrual cycles rather than estrous cycles.

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.

The placenta is an organ that develops in the uterus during pregnancy and provides oxygen and nutrients to the growing baby through the umbilical cord. It also removes waste products from the baby's blood. The placenta attaches to the wall of the uterus, and the baby's side of the placenta contains many tiny blood vessels that connect to the baby's circulatory system. This allows for the exchange of oxygen, nutrients, and waste between the mother's and baby's blood. After the baby is born, the placenta is usually expelled from the uterus in a process called afterbirth.

I am not aware of a medical definition for the term "buffaloes." The term generally refers to large, hoofed mammals that are native to Africa and Asia. In English language slang, the term "buffalo" is sometimes used to describe a lie or exaggeration, but this usage is not related to the medical field. If you have more context about where you encountered this term, I may be able to provide a more specific answer.

"Macaca mulatta" is the scientific name for the Rhesus macaque, a species of monkey that is native to South, Central, and Southeast Asia. They are often used in biomedical research due to their genetic similarity to humans.

"Pregnancy proteins" is not a standard medical term, but it may refer to specific proteins that are produced or have increased levels during pregnancy. Two common pregnancy-related proteins are:

1. Human Chorionic Gonadotropin (hCG): A hormone produced by the placenta shortly after fertilization. It is often detected in urine or blood tests to confirm pregnancy. Its primary function is to maintain the corpus luteum, which produces progesterone and estrogen during early pregnancy until the placenta takes over these functions.

2. Pregnancy-Specific beta-1 Glycoprotein (SP1): A protein produced by the placental trophoblasts during pregnancy. Its function is not well understood, but it may play a role in implantation, placentation, and protection against the mother's immune system. SP1 levels increase throughout pregnancy and are used as a marker for fetal growth and well-being.

These proteins have clinical significance in monitoring pregnancy progression, detecting potential complications, and diagnosing certain pregnancy-related conditions.

5-Alpha-Dihydroprogesterone, also known as 5α-DHP, is a metabolite of progesterone. It is formed in the body by the action of the enzyme 5-alpha-reductase on progesterone. 5-Alpha-Dihydroprogesterone is a weak androgen and has been found to have some effects on the development and maintenance of male sexual characteristics. It may also play a role in the regulation of the menstrual cycle in women. However, its precise physiological functions are not fully understood.

Metestrus is the second phase of the estrous cycle in animals, specifically referring to the period of sexual receptivity and ovulation. In humans, this phase corresponds to the luteal phase of the menstrual cycle. During metestrus, the corpus luteum, a temporary endocrine structure formed from the remains of the ovarian follicle after ovulation, produces progesterone, which prepares the uterus for potential implantation of a fertilized egg. The duration of metestrus varies among species and can last several days to a few weeks. It is followed by diestrus, the final phase of the estrous cycle, during which the corpus luteum regresses, and hormone levels drop, leading to the shedding of the uterine lining in non-pregnant individuals.

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.

Progestins are a class of steroid hormones that are similar to progesterone, a natural hormone produced by the ovaries during the menstrual cycle and pregnancy. They are often used in hormonal contraceptives, such as birth control pills, shots, and implants, to prevent ovulation and thicken the cervical mucus, making it more difficult for sperm to reach the egg. Progestins are also used in menopausal hormone therapy to alleviate symptoms of menopause, such as hot flashes and vaginal dryness. Additionally, progestins may be used to treat endometriosis, uterine fibroids, and breast cancer. Different types of progestins have varying properties and may be more suitable for certain indications or have different side effect profiles.

Northern blotting is a laboratory technique used in molecular biology to detect and analyze specific RNA molecules (such as mRNA) in a mixture of total RNA extracted from cells or tissues. This technique is called "Northern" blotting because it is analogous to the Southern blotting method, which is used for DNA detection.

The Northern blotting procedure involves several steps:

1. Electrophoresis: The total RNA mixture is first separated based on size by running it through an agarose gel using electrical current. This separates the RNA molecules according to their length, with smaller RNA fragments migrating faster than larger ones.

2. Transfer: After electrophoresis, the RNA bands are denatured (made single-stranded) and transferred from the gel onto a nitrocellulose or nylon membrane using a technique called capillary transfer or vacuum blotting. This step ensures that the order and relative positions of the RNA fragments are preserved on the membrane, similar to how they appear in the gel.

3. Cross-linking: The RNA is then chemically cross-linked to the membrane using UV light or heat treatment, which helps to immobilize the RNA onto the membrane and prevent it from washing off during subsequent steps.

4. Prehybridization: Before adding the labeled probe, the membrane is prehybridized in a solution containing blocking agents (such as salmon sperm DNA or yeast tRNA) to minimize non-specific binding of the probe to the membrane.

5. Hybridization: A labeled nucleic acid probe, specific to the RNA of interest, is added to the prehybridization solution and allowed to hybridize (form base pairs) with its complementary RNA sequence on the membrane. The probe can be either a DNA or an RNA molecule, and it is typically labeled with a radioactive isotope (such as ³²P) or a non-radioactive label (such as digoxigenin).

6. Washing: After hybridization, the membrane is washed to remove unbound probe and reduce background noise. The washing conditions (temperature, salt concentration, and detergent concentration) are optimized based on the stringency required for specific hybridization.

7. Detection: The presence of the labeled probe is then detected using an appropriate method, depending on the type of label used. For radioactive probes, this typically involves exposing the membrane to X-ray film or a phosphorimager screen and analyzing the resulting image. For non-radioactive probes, detection can be performed using colorimetric, chemiluminescent, or fluorescent methods.

8. Data analysis: The intensity of the signal is quantified and compared to controls (such as housekeeping genes) to determine the relative expression level of the RNA of interest. This information can be used for various purposes, such as identifying differentially expressed genes in response to a specific treatment or comparing gene expression levels across different samples or conditions.

'Labor, Obstetric' refers to the physiological process that occurs during childbirth, leading to the expulsion of the fetus from the uterus. It is divided into three stages:

1. The first stage begins with the onset of regular contractions and cervical dilation and effacement (thinning and shortening) until full dilation is reached (approximately 10 cm). This stage can last from hours to days, particularly in nulliparous women (those who have not given birth before).
2. The second stage starts with complete cervical dilation and ends with the delivery of the baby. During this stage, the mother experiences strong contractions that help push the fetus down the birth canal. This stage typically lasts from 20 minutes to two hours but can take longer in some cases.
3. The third stage involves the delivery of the placenta (afterbirth) and membranes, which usually occurs within 15-30 minutes after the baby's birth. However, it can sometimes take up to an hour for the placenta to be expelled completely.

Obstetric labor is a complex process that requires careful monitoring and management by healthcare professionals to ensure the safety and well-being of both the mother and the baby.

An abortifacient agent is a substance or drug that causes abortion by inducing the uterus to contract and expel a fetus. These agents can be chemical or herbal substances, and they work by interfering with the implantation of the fertilized egg in the uterine lining or by stimulating uterine contractions to expel the developing embryo or fetus.

Examples of abortifacient agents include misoprostol, mifepristone, and certain herbs such as pennyroyal, tansy, and black cohosh. It is important to note that the use of abortifacient agents can have serious health consequences, including infection, bleeding, and damage to the reproductive system. Therefore, it is essential to consult with a healthcare provider before using any abortifacient agent.

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.

Buserelin is a synthetic analogue of gonadotropin-releasing hormone (GnRH or LHRH), which is a hormonal drug used in the treatment of various conditions such as endometriosis, uterine fibroids, prostate cancer, and central precocious puberty.

By mimicking the action of natural GnRH, buserelin stimulates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland, which in turn regulates the production of sex hormones such as estrogen and testosterone.

However, prolonged use of buserelin leads to downregulation of GnRH receptors and a decrease in FSH and LH secretion, resulting in reduced levels of sex hormones. This property is exploited in the treatment of hormone-dependent cancers such as prostate cancer, where reducing testosterone levels can help slow tumor growth.

Buserelin is available in various forms, including nasal sprays, implants, and injectable solutions, and its use should be under the supervision of a healthcare professional due to potential side effects and the need for careful monitoring of hormone levels during treatment.

17-α-Hydroxyprogesterone is a naturally occurring hormone produced by the adrenal glands and, in smaller amounts, by the ovaries and testes. It is an intermediate in the biosynthesis of steroid hormones, including cortisol, aldosterone, and sex hormones such as testosterone and estrogen.

In a medical context, 17-α-Hydroxyprogesterone may also refer to a synthetic form of this hormone that is used in the treatment of certain medical conditions. For example, a medication called 17-alpha-hydroxyprogesterone caproate (17-OHP) is used to reduce the risk of preterm birth in women who have previously given birth prematurely. It works by suppressing uterine contractions and promoting fetal lung maturity.

It's important to note that 17-alpha-Hydroxyprogesterone should only be used under the supervision of a healthcare provider, as it can have side effects and may interact with other medications.

Androstenedione is a steroid hormone produced by the adrenal glands, ovaries, and testes. It is a precursor to both male and female sex hormones, including testosterone and estrogen. In the adrenal glands, it is produced from cholesterol through a series of biochemical reactions involving several enzymes. Androstenedione can also be converted into other steroid hormones, such as dehydroepiandrosterone (DHEA) and estrone.

In the body, androstenedione plays an important role in the development and maintenance of secondary sexual characteristics, such as facial hair and a deep voice in men, and breast development and menstrual cycles in women. It also contributes to bone density, muscle mass, and overall physical strength.

Androstenedione is available as a dietary supplement and has been marketed as a way to boost athletic performance and increase muscle mass. However, its effectiveness for these purposes is not supported by scientific evidence, and it may have harmful side effects when taken in high doses or for extended periods of time. Additionally, the use of androstenedione as a dietary supplement is banned by many sports organizations, including the International Olympic Committee and the National Collegiate Athletic Association.

An ovarian cyst is a sac or pouch filled with fluid that forms on the ovary. Ovarian cysts are quite common in women during their childbearing years, and they often cause no symptoms. In most cases, ovarian cysts disappear without treatment over a few months. However, larger or persistent cysts may require medical intervention, including surgical removal.

There are various types of ovarian cysts, such as functional cysts (follicular and corpus luteum cysts), which develop during the menstrual cycle due to hormonal changes, and non-functional cysts (dermoid cysts, endometriomas, and cystadenomas), which can form due to different causes.

While many ovarian cysts are benign, some may have malignant potential or indicate an underlying medical condition like polycystic ovary syndrome (PCOS). Regular gynecological check-ups, including pelvic examinations and ultrasounds, can help detect and monitor ovarian cysts.

Progesterone reductase is not a widely recognized or used term in medical literature. However, based on the terms "progesterone" and "reductase," it can be inferred that progesterone reductase might refer to an enzyme responsible for reducing or converting progesterone into another form through a reduction reaction.

Progesterone is a steroid hormone involved in the menstrual cycle, pregnancy, and embryogenesis. Reductases are enzymes that catalyze the transfer of electrons from a donor to an acceptor, often resulting in the reduction of a substrate. In this context, progesterone reductase could potentially refer to an enzyme responsible for reducing progesterone into a different steroid hormone or metabolite.

However, it is essential to note that there is no widely accepted or established definition of "progesterone reductase" in medical literature. If you are looking for information on a specific enzyme related to progesterone metabolism, I would recommend consulting primary scientific literature or seeking guidance from a medical professional.

Ovulation detection refers to the process of identifying the time period during which an ovary releases an oocyte (mature egg) from its follicle, ready for fertilization. This is a crucial aspect of reproductive health and assisted reproduction technologies (ART), such as in vitro fertilization (IVF).

There are several methods to detect ovulation, including:

1. Ovulation Predictor Kits (OPKs): These are home-use test kits that detect the surge of luteinizing hormone (LH) in urine, which occurs 24-36 hours prior to ovulation.
2. Basal Body Temperature (BBT) Charting: This involves tracking and recording daily basal body temperature (the lowest temperature attained by the body during rest), as it tends to rise slightly after ovulation due to increased progesterone levels.
3. Hormonal Monitoring: Blood tests can be used to measure hormone levels, such as estrogen and progesterone, throughout a menstrual cycle to detect ovulation.
4. Transvaginal Ultrasound: This imaging technique is often used in clinical settings to monitor follicular development and determine the exact time of ovulation by observing changes in the ovarian follicle and endometrial lining.
5. Saliva Ferning Tests: A microscope is used to examine the patterns formed by dried saliva, which can indicate increased estrogen levels prior to ovulation.

Accurate ovulation detection helps individuals or couples trying to conceive optimize their chances of success and provides valuable information for healthcare providers in managing reproductive health issues.

Anestrus is a term used in veterinary medicine to describe the period of sexual quiescence in female animals, during which they do not exhibit estrous cycles. This phase is characterized by low levels of reproductive hormones and is seen in some species as a part of their natural reproductive cycle, while in others it may indicate an abnormality or underlying health issue.

For example, in dogs, anestrus is the period between heat cycles when the reproductive system is relatively inactive. In contrast, in domestic cats, continuous estrous cycling is the norm, and they do not typically exhibit an anestrus phase.

In some cases, anestrus may be induced by factors such as poor nutrition, stress, or illness, and it can have negative consequences for an animal's reproductive health if it persists for too long. If an animal is experiencing prolonged anestrus or other reproductive issues, it is important to consult with a veterinarian for proper diagnosis and treatment.

"Swine" is a common term used to refer to even-toed ungulates of the family Suidae, including domestic pigs and wild boars. However, in a medical context, "swine" often appears in the phrase "swine flu," which is a strain of influenza virus that typically infects pigs but can also cause illness in humans. The 2009 H1N1 pandemic was caused by a new strain of swine-origin influenza A virus, which was commonly referred to as "swine flu." It's important to note that this virus is not transmitted through eating cooked pork products; it spreads from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes.

Prostaglandins are naturally occurring, lipid-derived hormones that play various important roles in the human body. They are produced in nearly every tissue in response to injury or infection, and they have diverse effects depending on the site of release and the type of prostaglandin. Some of their functions include:

1. Regulation of inflammation: Prostaglandins contribute to the inflammatory response by increasing vasodilation, promoting fluid accumulation, and sensitizing pain receptors, which can lead to symptoms such as redness, heat, swelling, and pain.
2. Modulation of gastrointestinal functions: Prostaglandins protect the stomach lining from acid secretion and promote mucus production, maintaining the integrity of the gastric mucosa. They also regulate intestinal motility and secretion.
3. Control of renal function: Prostaglandins help regulate blood flow to the kidneys, maintain sodium balance, and control renin release, which affects blood pressure and fluid balance.
4. Regulation of smooth muscle contraction: Prostaglandins can cause both relaxation and contraction of smooth muscles in various tissues, such as the uterus, bronchioles, and vascular system.
5. Modulation of platelet aggregation: Some prostaglandins inhibit platelet aggregation, preventing blood clots from forming too quickly or becoming too large.
6. Reproductive system regulation: Prostaglandins are involved in the menstrual cycle, ovulation, and labor induction by promoting uterine contractions.
7. Neurotransmission: Prostaglandins can modulate neurotransmitter release and neuronal excitability, affecting pain perception, mood, and cognition.

Prostaglandins exert their effects through specific G protein-coupled receptors (GPCRs) found on the surface of target cells. There are several distinct types of prostaglandins (PGs), including PGD2, PGE2, PGF2α, PGI2 (prostacyclin), and thromboxane A2 (TXA2). Each type has unique functions and acts through specific receptors. Prostaglandins are synthesized from arachidonic acid, a polyunsaturated fatty acid derived from membrane phospholipids, by the action of cyclooxygenase (COX) enzymes. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, inhibit COX activity, reducing prostaglandin synthesis and providing analgesic, anti-inflammatory, and antipyretic effects.

Penile erection is a physiological response that involves the engagement of the corpus cavernosum and spongiosum (erectile tissue) of the penis with blood, leading to its stiffness and rigidity. This process is primarily regulated by the autonomic nervous system and is influenced by factors such as sexual arousal, emotional state, and certain medications or medical conditions. A penile erection may also occur in non-sexual situations, such as during sleep (nocturnal penile tumescence) or due to other physical stimuli.

Once the corpus luteum regresses the remnant is known as corpus albicans. The corpus luteum is essential for establishing and ... The corpus luteum (Latin for "yellow body"; PL: corpora lutea) is a temporary endocrine structure in female ovaries involved in ... Corpus luteum cyst: hemorrhage into persistent corpus luteum. Commonly regresses spontaneously. List of distinct cell types in ... From this point on, the corpus luteum is called the corpus luteum graviditatis.[citation needed] The introduction of ...
... s may contain blood and other fluids. The physical shape of a corpus luteum cyst may appear as an enlargement ... the corpus luteum usually breaks down and disappears. It may, however, fill with fluid or blood, causing the corpus luteum to ... A corpus luteum cyst is a type of ovarian cyst which may rupture about the time of menstruation, and take up to three months to ... Corpus luteum cysts are a normal part of the menstrual cycle. They can, however, grow to almost 10 cm (4 inches) in diameter ...
During four phases of its estrous cycle, mean weight of corpus luteum has been found to be 1.23±0.22g (metestrus), 3.15±0.10g ( ... The female is not yet sexually receptive; the old corpus luteum degenerates; the uterus and the vagina distend and fill with ... The signs of estrogen stimulation subside and the corpus luteum starts to form. The uterine lining begins to appear. In the ... The following day, metestrus, is called early diestrus or diestrus I. During this day, the corpora lutea grow to a maximal ...
Between 7 and 9 weeks, the placenta begins to produce progesterone in place of the corpus luteum in a process called the luteal ... If ovulation does not occur and the corpus luteum does not develop, levels of progesterone may be low, leading to anovulatory ... At first, the source is the corpus luteum that has been "rescued" by the presence of human chorionic gonadotropin (hCG) from ... Up to this point, progesterone, known generically as corpus luteum hormone, had been being referred to by several groups by ...
The corpus luteum secretes progesterone. Depending on breed, on average, 16% of mares have double ovulations, allowing them to ... It decreases 12-15 days after ovulation, when the corpus luteum begins to decrease in size. Prostaglandin: secreted by the ... causes luteolysis and prevents the corpus luteum from secreting progesterone eCG - equine chorionic gonadotropin - also called ...
Corpus luteum cysts appear after ovulation. The corpus luteum is the remnant of the follicle after the ovum has moved to the ... A corpus luteum that is more than 3 cm is defined as cystic. Theca lutein cysts occur within the thecal layer of cells ... For the corpus luteum, a dominant ovulating follicle that typically appears as a cyst with circumferentially thickened walls ... Most ovarian cysts are related to ovulation, being either follicular cysts or corpus luteum cysts. Other types include cysts ...
FP receptor activation contributes to the regression of the corpus luteum and thereby the estrus cycle in many species of farm ... Luteal cells of corpus luteum. The FP receptor is the least selective of the prostenoid receptors in that it is responsive to ... follicles and corpus luteum). Studies in mice indicate that FP mRNA and/or protein is expressed in diverse tissues including ... That is, these FP-/- mice fail to enter labor even if induced by oxytocin due to a failure in copus luteum regression and ...
... hCG prevents degeneration of the corpus luteum. Progesterone serves to maintain the integrity of the uterine lining and, until ... it is aided by the corpus luteum graviditatis. The syncytiotrophoblast lacks proliferative capacity and instead is maintained ...
Rupture of corpus luteum in some cases. Less commonly, bleeding due to a perforated gastric ulcer. Bleeding due to rupture of ...
... the follicle from which the oocyte was released becomes the corpus luteum. The corpus luteum is the last stage of the ovarian ... Progesterone levels also decrease during menopause because without any follicles, there is no development of the corpus luteum ... Oliver R, Pillarisetty LS (2022). "Anatomy, Abdomen and Pelvis, Ovary Corpus Luteum". StatPearls. Treasure Island (FL): ... If conception does not occur, then it will be shed and is known as the corpus albicans. It has been observed that this ...
Luteolysis is the regression of the corpus luteum. The process is identified by the decline of progesterone and it signifies ... Progesterone released from the corpus luteum is promoted by human chorionic gonadotrophin (hCG) produced by the cells of the ... Pregnancy maintenance relies on the continued production of progesterone which is initially produced by the corpus luteum (CL ... essential for the maintenance of the corpus luteum. Interferon tau is secreted by the trophectoderm of the blastocyst from ...
Ott, I.; Scott, J. C. (1910). "The galactagogue action of the thymus and corpus luteum". Experimental Biology and Medicine. 8 ( ... He identified the corpora striata as the region of the brain responsible for temperature regulation. He studied pituitary ... Ott conducted animal experiments and contributed to the understanding of the regulation of body temperature by the corpora ...
Weekes, H.C. (1934). "The corpus luteum in certain oviparous and viviparous reptiles". Proc. Linn. Soc. N.S.W. 69: 380-391. ...
1999). "Immunolocalization of glutaredoxin in the human corpus luteum". Mol. Hum. Reprod. 5 (10): 914-9. doi:10.1093/molehr/ ...
2018). "Regulation of the porcine corpus luteum during pregnancy". Reproduction. 156 (3): R57-R67. doi:10.1530/rep-17-0662. ... in pigs occurs on days 11 to 12 of pregnancy and is marked by progesterone production from a functioning corpus luteum (CL). To ...
"Physiology of the corpus luteum, V: the preparation and some chemical properties of progestin, a hormone of the corpus luteum ... On May 5, I had the crystalline corpus luteum hormone. On May 18, my daughter, Lucille, was born. My friends gave me double ...
The main function of hCG is to sustain the ovarian corpus luteum during pregnancy past the time it would normally decay as part ... For the first 7-9 weeks in humans, the corpus luteum secretes the progesterone necessary to maintain the viability of the ... Csapo AI, Pulkkinen MO, Ruttner B, Sauvage JP, Wiest WG (April 1972). "The significance of the human corpus luteum in pregnancy ...
"Über einen Abbau des Stigmasterins zu corpus-luteum-wirksamen Stoffen; ein Beitrag zur Konstitution des Corpusluteum-Hormons ( ...
1999 Mar; 83(1):115-9. Frobenius W., "Ludwig Fraenkel, corpus luteum and discovery of progesterone." Zentralbl Gynakol. 1998; ...
... which is also secreted by the corpus luteum, contributes to FSH inhibition. Progesterone, secreted by the corpus luteum, ... A rise in pituitary FSH caused by the disintegration of the corpus luteum at the conclusion of a menstrual cycle precipitates ... Following ovulation, LH stimulates the formation of the corpus luteum. Estrogen has since dropped to negative stimulatory ... The ruptured follicle will undergo a dramatic transformation into the corpus luteum, a steroidiogenic cluster of cells that ...
After rupturing, the follicle is turned into a corpus luteum. In a larger perspective, the whole folliculogenesis from ...
Due to these hormonal changes, the corpus luteum gets destroyed. The elevated level of FSH helps to recruit a cohort of the FSH ...
... corpus candicans, or simply as albicans) is the regressed form of the corpus luteum. As the corpus luteum is being broken down ... A well-developed vascular supply also grows into the corpus luteum. The granulosa cells in the corpus luteum develop extensive ... The corpus albicans (Latin for "whitening body"; also known as atretic corpus luteum, ... The corpus luteum normally grows to about 1.5 centimeters in diameter, reaching this stage of development 7 to 8 days after ...
Interestingly these knockout mice exhibit the stochastic effect; the corpus luteum will form in some, but not in all. This ... This can cause malformation or potential no formation of the corpus luteum leading to infertility, smaller litters, and fewer ...
"Mechanisms controlling the function and life span of the corpus luteum". Physiological Reviews. 80 (1): 1-29. doi:10.1152/ ...
... is expressed in the ovary and corpus luteum, where its expression is induced by progesterone and during pregnancy, ... Cai Z, Stocco C (Dec 2005). "Expression and regulation of progestin membrane receptors in the rat corpus luteum". Endocrinology ...
Paraspeckles form a significant portion of the corpus luteum of the ovary; in Neat1 impaired mice, corpus luteum formation is ... December 2014). "The lncRNA Neat1 is required for corpus luteum formation and the establishment of pregnancy in a subpopulation ...
Corpora lutea are found only in mammals, and in some elasmobranch fish; in other species, the remnants of the follicle are ... Also in the cortex is the corpus luteum derived from the follicles. The innermost layer is the ovarian medulla. It can be hard ... The follicle remains functional and reorganizes into a corpus luteum, which secretes progesterone in order to prepare the ...
In the human ovary, H2 relaxin is produced by the corpus luteum and by Granulosa cells from large antral follicles. Research ... This hormone stimulates the Corpus Luteum to produce progesterone to maintain pregnancy. Therefore, hCG plays a role in human ...
... im Besonderen des Hormons des Corpus luteum. I. Der biologische Test für das Luteumhormon (das spezielle Hormon des Corpus ... luteum) am infantilen Kaninchen". Zentralblatt für Gynäkologie. 54: 2757-2770. "Clauberg's method, alt. Clauberg's test". ...
Once the corpus luteum regresses the remnant is known as corpus albicans. The corpus luteum is essential for establishing and ... The corpus luteum (Latin for "yellow body"; PL: corpora lutea) is a temporary endocrine structure in female ovaries involved in ... Corpus luteum cyst: hemorrhage into persistent corpus luteum. Commonly regresses spontaneously. List of distinct cell types in ... From this point on, the corpus luteum is called the corpus luteum graviditatis.[citation needed] The introduction of ...
... cells in dispersed rhesus monkey corpora lutea (CL) after progesterone (P4) levels had fallen below 0.3 ng/ml for ≥3 days ... in immune cell distribution and their cytokine/chemokine production during regression of the rhesus macaque corpus luteum. †. ... in immune cell distribution and their cytokine/chemokine production during regression of the rhesus macaque corpus luteum. †. ... in immune cell distribution and their cytokine/chemokine production during regression of the rhesus macaque corpus luteum. †. ...
Sus Scrofa Corpus Luteum (UNII: 94X749MHSP) (Sus Scrofa Corpus Luteum - UNII:94X749MHSP) Sus Scrofa Corpus Luteum. 200 [kp_C] ... Adrenal gland 6X 200K, Cholesterinum 6X 200K, Corpus luteum 6X 200K, Estrogen 12X 200K, Hypothalamus 6X 200K, Melatonin 6X 200K ... Label: FEMALE PLUS- bos taurus adrenal gland, sus scrofa adrenal gland, cholesterol, sus scrofa corpus luteum, esterified ... bos taurus adrenal gland, sus scrofa adrenal gland, cholesterol, sus scrofa corpus luteum, esterified estrogen, bos taurus ...
Corpora lutea (n = 3-5/stage) were collected during the early (3-5 days post-luteinizing hormone surge), mid- (6-8 days), mid- ... Angiopoietin-1, Angiopoietin-2, Animals, Corpus Luteum, Endothelial Growth Factors, Female, Gene Expression Regulation, ... Changes in expression of vascular endothelial growth factor and angiopoietin-1 and -2 in the macaque corpus luteum during the ... Changes in expression of vascular endothelial growth factor and angiopoietin-1 and -2 in the macaque corpus luteum during the ...
... corpus luteum - central lacuna & more Bovis resources at Vetlexicon. Over 28,000 peer-reviewed resources: Canis, Lapis, Equis, ... Ultrasonography: corpus luteum - central lacuna. Subscribe To View. This article is available to subscribers. Try a free trial ...
The corpus luteum (Latin for "yellow body"; PL: corpora lutea) is a temporary endocrine structure in female ovaries involved in ... Corpus luteum cyst: hemorrhage into persistent corpus luteum. Commonly regresses spontaneously.. See also[edit]. List of ... The corpus luteum is essential for establishing and maintaining pregnancy in females. The corpus luteum secretes progesterone, ... From this point on, the corpus luteum is called the corpus luteum graviditatis. ...
3. The Likelihood of a Novel Role of RAS in the Ovarian Corpus Luteum. The ovarian corpus luteum is a transient endocrine gland ... In the early and mid-luteal phase of the corpus luteum life cycle, the ovarian corpus luteum undergoes a high level of ... However, those essential proteins are not involved only in corpus luteum formation but also in the regulation of corpus luteum ... also plays a crucial factor in the angiogenesis and neovascularization of ovarian corpus luteum [59]. In the corpus luteum ...
... to provide an overview of the types of endothelial cells present in the corpus luteum and their involvement in corpus luteum ... The granulosa cells and theca cells of the developing antral follicle and the steroidogenic cells of the corpus luteum produce ... Available evidence indicates that microvascular endothelial cells of the corpus luteum are not alike, and may differ during the ... Following ovulation the neovascularization during the early stages of corpus luteum development has been compared to the rapid ...
Todays episode is all about progesterone. Find out how to tell if your progesterone is low by looking at your menstrual cycle chart, and how to boost your levels if theyre low. My Fertility Awareness Programs are designed to help you to master Fertility Awareness and take a deep dive into your cycles. Gain confidence… Read More ». ...
Corpus luteum cysts are often identified during imaging procedures in early pregnancy. Theyre one of the most common types of ...
C-kinase in the corpus luteum suggest that the control of C-kinase activity. is related to the function of the corpus luteum. ... corpora lutea. The enzyme will be purified with the objectives of 1). determining the specific co-factors required for C-kinase ... of the corpus luteum and 2) determining if enzyme activity is regulated by. LH or other factors known to regulate luteal ... Although many of the effects of luteinizing hormone (LH) in the corpus. luteum are thought to be mediated by cAMP, the exact ...
Analysis of microarray data from the macaque corpus luteum; the search for common themes in primate luteal regression. Title. ... Analysis of microarray data from the macaque corpus luteum; the search for common themes in primate luteal regression. ... Analysis of microarray data from the macaque corpus luteum; the search for common themes in primate luteal regression ...
corpus luteum?. 13. Be able to define complications of menstruation such as. amenorrhea, anovulatory cycles, polycystic ovary ...
The ultra structure of luteal cells and the proportion of the different cell types in the functional corpus luteum of the goat ... Two luteal cell types, large and small, were present in the corpus luteum of this species. The large more rounded luteal cell ... The Ultrastructure of the Corpus Luteum of the Goat. Pertanika, 8 (2). pp. 215-222. ...
The maintenance of early pregnancy requires a fully functional corpus luteum (CL) that is not susceptible to regression ... The maintenance of early pregnancy requires a fully functional corpus luteum (CL) that is not susceptible to regression ... Townson, D.H. Immune cell-endothelial cell interactions in the bovine corpus luteum. Integr Comp Biol 46:1055-1059 (2006). ...
Localization of lipid peroxidation-derived protein epitopes in the porcine corpus luteum. Biology of reproduction. 1997;57(6): ... Localization of lipid peroxidation-derived protein epitopes in the porcine corpus luteum. / Brannian, J. D.; Zhao, Y.; Burbach ... N2 - Reactive oxygen species (ROS) generated within the corpus luteum (CL) are believed to play an integral role in luteolysis ... AB - Reactive oxygen species (ROS) generated within the corpus luteum (CL) are believed to play an integral role in luteolysis ...
This is called a corpus luteum cyst. This type of cyst may contain a small amount of blood. This cyst makes progesterone and ... These are more common with corpus luteum cysts. Spotting or bleeding may occur with some cysts. ...
Corpus luteum: Corpus luteum cysts can form when the empty follicle sac doesnt shrink after ovulation. Instead, the sac ... leading to a corpus luteum cyst. These cysts typically grow to about 3 cm. (about 1.18 inches). ...
Evaluation was restricted to one corpus luteum per dog. From each corpus luteum 3 slides were prepared, evaluation followed ... Pro Hund wurde ein Paraffinblock, d. h. ein Corpus luteum, herangezogen. Von diesem Block wurden 3 Schnitte gefärbt. ... Four bitches of different breeds were ovariohysterectomized on days 5, 15, 25, 35 and 45 after ovulation, corpora lutea were ... Darstellung von Estradiol-17beta- und Progesteronrezeptoren im Corpus luteum der Hündin zu definierten Zeitpunkten im Östrus ...
... unless a corpus luteum is still palpable) ...
... due to the corpus luteum. At the end of the secretory phase the corpus luteum degenerates, and progesterone levels fall. This ... If fertilization and implantation do not occur the corpus luteum degenerates into a corpus albicans, and progesterone levels ... The corpus luteum degenerates causing plasma estrogen and progesterone levels to decrease and in turn causes menstruation. ... Progesterone is produced by the corpus luteum (the follicle after ovulation) and enriches the uterus with a thick lining of ...
... pregnancy must be considered as a cause of the persistence of the corpus luteum. Prolonged maintenance of the corpus luteum has ... Regression of the corpus luteum as in cattle following treatment with some estrogen esters may not be noticed in all species; ... CAUTIONS: In the case of prolonged persistence of the corpus luteum in cows, thorough examination should also be made of the ... Pregnancy may be the prime reason for either anestrus or the persistence of the corpus luteum. Since pregnancy may be ...
Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.. Title. ... Animals, Base Sequence, Camelids, New World, Corpus Luteum, Estrogen Receptor alpha, Estrogen Receptor beta, Estrogens, Female ... Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.. ... Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas. ...
CONGENER-SPECIFIC MECHANISM OF POLICHLORINATED BIPHENYLS (PCB 126 AND PCB 153) ACTION ON THE CORPUS LUTEUM. Publication ...
Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.. Title. ... Animals, Base Sequence, Camelids, New World, Corpus Luteum, Estrogen Receptor alpha, Estrogen Receptor beta, Estrogens, Female ... Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.. ... Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas. ...
b. the corpus luteum. c. the endometrial lining of the uterus. d. surface cells from the vagina. e. blood from the blood ... b. the corpus luteum. c. the endometrial lining of the uterus. d. surface cells from the. Biology Posted : 2018-05-07. Updated ... b. the corpus luteum.. c. the endometrial lining of the uterus.. d. surface cells from the vagina.. e. blood from the blood ...
Dynamics of Immune Cell Types Within the Macaque Corpus Luteum During the Menstrual Cycle: Role of Progesterone1. Title. ... Dynamics of Immune Cell Types Within the Macaque Corpus Luteum During the Menstrual Cycle: Role of Progesterone1. ... Dynamics of Immune Cell Types Within the Macaque Corpus Luteum During the Menstrual Cycle: Role of Progesterone1 ...
Ultrasonography was used to scan ovaries to determine development of ovulatory follicle (OF) and formation of corpus luteum (CL ... Additional growth of dominant follicle during synchronized ovulatory cycle affects ovulatory follicle size, corpus luteum ...
Haemoperitoneum due to ruptured corpus luteum! managed conservatively-2 case reports and review of literature Authors. * Anjum ... Ho WK, Wang YF, Wu HH, Tsai HD, Chen TH, Chen M. Ruptured corpus luteum with hemoperitoneum: case characteristics and ... Murao H, Kinjyo, K. Demura T. Conservative therapy for corpus luteum hemorrhage, a review of 116 cases. Clin. Gynecol. Obstet. ... Gupta N, Dadhwal V, Deka D, Jain SK, Mittal S. Corpus luteum hemorrhage: rare complication of congenital and acquired ...
  • While the oocyte (later the zygote if fertilization occurs) traverses the Fallopian tube into the uterus, the corpus luteum remains in the ovary. (wikipedia.org)
  • The corpus luteum is a temporary endocrine gland in the ovary. (encyclopedia.pub)
  • Thus, we have reviewed the role of RAS protein related to the biological events of the corpus luteum in the ovary. (encyclopedia.pub)
  • The potential clinical applications of research directed on corpus luteum endothelial cells are intriguing considering reproductive processes in which vascular dysfunctions may play a role such as ovarian failure, polycystic ovary syndrome (PCOS), and ovarian hyperstimulation syndrome (OHSS). (biomedcentral.com)
  • Estradiol is produced primarily in the ovary (follicle, corpus luteum), but small quantities are also formed in the testes and in the adrenal cortex, as well as in fat cells. (cdc.gov)
  • a corpus luteum cyst was present in the left ovary. (cdc.gov)
  • Okay, so this is where things get a bit more scientific, but Telfer breaks it down: 'Once an egg is released from an ovary at ovulation, the cells that were previously supporting the egg [the ovarian follicle] change function and turn into the corpus luteum,' she says. (yahoo.com)
  • This was proved by presence of the corpus luteum in the contralateral ovary in 50% of ectopic pregnancy. (gfmer.ch)
  • PL: corpora lutea) is a temporary endocrine structure in female ovaries involved in the production of relatively high levels of progesterone, and moderate levels of estradiol, and inhibin A. It is the remains of the ovarian follicle that has released a mature ovum during a previous ovulation. (wikipedia.org)
  • The corpus luteum is colored as a result of concentrating carotenoids (including lutein) from the diet and secretes a moderate amount of estrogen that inhibits further release of gonadotropin-releasing hormone (GnRH) and thus secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). (wikipedia.org)
  • The corpus luteum develops from an ovarian follicle during the luteal phase of the menstrual cycle or oestrous cycle, following the release of a secondary oocyte from the follicle during ovulation. (wikipedia.org)
  • The follicle first forms a corpus hemorrhagicum before it becomes a corpus luteum, but the term refers to the visible collection of blood, left after rupture of the follicle, that secretes progesterone. (wikipedia.org)
  • The granulosa cells and theca cells of the developing antral follicle and the steroidogenic cells of the corpus luteum produce and respond to angiogenic factors and vasoactive peptides. (biomedcentral.com)
  • Corpus luteum cysts can form when the empty follicle sac doesn't shrink after ovulation. (healthline.com)
  • The corpus luteum is a temporary endocrine, or hormone-producing, gland that forms from the empty ovarian follicle after ovulation. (medicalnewstoday.com)
  • These cysts develop from the corpus luteum (which forms from the dominant follicle after ovulation). (msdmanuals.com)
  • What are the symptoms of a corpus luteum cyst? (helpof.com)
  • How can I prevent getting a corpus luteum cyst? (helpof.com)
  • How is a corpus luteum cyst diagnosed? (helpof.com)
  • How does a corpus luteum cyst affect my body? (helpof.com)
  • Does a corpus luteum cyst mean pregnancy? (helpof.com)
  • When should I seek care for a corpus luteum cyst? (helpof.com)
  • This is called a corpus luteum cyst. (medlineplus.gov)
  • Instead, the sac becomes sealed off and fills with fluid, leading to a corpus luteum cyst. (healthline.com)
  • Fiaschetti V, Ricci A. Hemoperitoneum from Corpus Luteal Cyst Rupture: A Practical Approach in Emergency Room Case Rep Emerg Med. (ijrcog.org)
  • In the absence of a positive pregnancy test result, fresh blood suggests a corpus luteum hemorrhage, old blood suggests a ruptured endometrioma (chocolate cyst), purulent fluid suggests acute pelvic inflammatory disease (PID), and sebaceous fluid indicates a dermoid cyst. (medscape.com)
  • In the ovarian cycle, repeated patterns of specific cellular proliferation, differentiation, and transformation occur that accompany the formation and regression of the corpus luteum. (encyclopedia.pub)
  • Moreover, RAS and RAS GTPases are changed in the development and regression of the corpus luteum. (encyclopedia.pub)
  • The cyclic nature of the capillary bed in the corpus luteum offers a unique experimental model to examine the life cycle of endothelial cells, involving discrete physiologically regulated steps of angiogenesis, blood vessel maturation and blood vessel regression. (biomedcentral.com)
  • On the other end of the spectrum, the microvascular endothelial cells are the first cells to undergo apoptosis at the onset of corpus luteum regression. (biomedcentral.com)
  • This review is designed to provide an overview of the types of endothelial cells present in the corpus luteum and their involvement in corpus luteum development and regression. (biomedcentral.com)
  • The contributions of vasoactive peptides generated by the luteal endothelin-1 and the renin-angiotensin systems are discussed in context with the function of endothelial cells during corpus luteum formation and regression. (biomedcentral.com)
  • Collectively, these studies demonstrate that the rate of endothelial cell proliferation is highest during corpus luteum formation, then decreases and remains low during the mid-luteal phase and structural regression of the corpus luteum. (biomedcentral.com)
  • The maintenance of early pregnancy requires a fully functional corpus luteum (CL) that is not susceptible to regression following fertilization, yet the cellular mechanisms of luteal regression are not clearly understood. (unh.edu)
  • It has been demonstrated that some estrogen esters will cause regression of the corpus luteum in cycling, pregnant or hysterectomized cattle. (drugs.com)
  • Separation of the gestational sac from the tubal wall leads to its degeneration, and fall of hCG level, regression of the corpus luteum and subsequent drop in the oestrogen and progesterone level. (gfmer.ch)
  • How common are corpus luteum cysts? (helpof.com)
  • Corpus luteum cysts are often identified during imaging procedures in early pregnancy. (helpof.com)
  • Do corpus luteum cysts go away? (helpof.com)
  • What causes corpus luteum cysts? (helpof.com)
  • Who does corpus luteum cysts affect? (helpof.com)
  • These are more common with corpus luteum cysts. (medlineplus.gov)
  • Corpus luteum cysts are less prevalent than follicular cysts. (medscape.com)
  • Benign ovarian masses include functional cysts (eg, corpus luteum cysts) and neoplasms (eg, benign teratomas). (msdmanuals.com)
  • Hemorrhagic corpus luteum cysts may cause pain or signs of peritonitis, particularly when they rupture. (msdmanuals.com)
  • Ovaries were removed and prepared for histological evaluation and tabulation of corpora lutea. (cdc.gov)
  • Corpora lutea were significantly reduced in ovaries from these mice. (cdc.gov)
  • The follicular theca cells luteinize into small luteal cells (thecal-lutein cells) and follicular granulosa cells luteinize into large luteal cells (granulosal-lutein cells) forming the corpus luteum. (wikipedia.org)
  • To determine the temporal expression of vascular growth factors during the lifespan of the primate corpus luteum, experiments were designed to detect mRNA for vascular endothelial growth factor (VEGF), angiopoietin (Ang)-1 and Ang-2 and to localize protein expression for VEGF in macaque luteal tissue during the menstrual cycle. (oregonstate.edu)
  • Corpora lutea (n = 3-5/stage) were collected during the early (3-5 days post-luteinizing hormone surge), mid- (6-8 days), mid-late (10-12 days), and late (14-16 days) luteal phase and at menstruation (17-18 days). (oregonstate.edu)
  • The physiological role for C-kinase will be examined by 1) determining whether or not enzyme activity varies throughout the life span of the corpus luteum and 2) determining if enzyme activity is regulated by LH or other factors known to regulate luteal function. (nebraska.edu)
  • The ultra structure of luteal cells and the proportion of the different cell types in the functional corpus luteum of the goat were studied using the electron microscope. (upm.edu.my)
  • Two luteal cell types, large and small, were present in the corpus luteum of this species. (upm.edu.my)
  • During the luteal phase of the cycle, the source of the estradiol is the corpus luteum. (proprofs.com)
  • A luteal phase defect is referring to a fault in the corpus luteum's ability to produce enough progesterone. (yahoo.com)
  • In basic terms, a luteal phase defect is when this corpus luteum does not produce enough progesterone, or when the second phase of a cycle after ovulation isn't supported well. (yahoo.com)
  • The corpus luteum is essential for establishing and maintaining pregnancy in females. (wikipedia.org)
  • The regulation of endothelial cell proliferation in the corpus luteum of pregnancy is less clear. (biomedcentral.com)
  • Pregnancy may be the prime reason for either anestrus or the persistence of the corpus luteum. (drugs.com)
  • As indicated earlier, pregnancy must be considered as a cause of the persistence of the corpus luteum. (drugs.com)
  • The response of the corpus luteum of pregnancy may differ with different estrogen esters. (drugs.com)
  • In the absence of a pregnancy or a detectable uterine malfunction, repeated rectal palpations will be required to establish a diagnosis of persistent corpus luteum. (drugs.com)
  • Because estrogen may be involved in maternal recognition of pregnancy and embryonic migration in llamas, expression of estrogen receptor subtypes alpha (ERalpha) and beta (ERbeta) was evaluated in corpus luteum (CL), endometrium, and uterus using relative RT-PCR. (oregonstate.edu)
  • Shalash (1965) stated that without pregnancy there is no formation of a corpus luteum. (fao.org)
  • The corpus luteum becomes the main source of progesterone that is needed to maintain a pregnancy immediately after fertilization and implantation. (medicalnewstoday.com)
  • In the case of prolonged persistence of the corpus luteum in cows, thorough examination should also be made of the uterus to determine the presence of endometritis or a fetus. (drugs.com)
  • Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas. (oregonstate.edu)
  • The corpus luteum prepares the uterus to receive a fertilized egg. (proprofs.com)
  • Following ovulation the neovascularization during the early stages of corpus luteum development has been compared to the rapid angiogenesis observed during tumor formation. (biomedcentral.com)
  • Bei jeweils 4 Hündinnen unterschiedlicher Rassen wurden an den Tagen 5, 15, 25, 35 und 45 nach der Ovulation die Ovarien mittelsOvariohysterektomie entnommen, die Corpora lutea separiert, und für die Immunhistochemie in 4% Lilliformol fixiert und anschließend inParaffin eingebettet. (uni-giessen.de)
  • No secretory changes are observed after menopause, because no ovulation occurs and therefore no corpus luteum forms to produce progesterone. (medscape.com)
  • The corpus luteum secretes progesterone, which is a steroid hormone responsible for the decidualization of the endometrium (its development) and maintenance, respectively. (wikipedia.org)
  • Tresch DD, Halverson G. Ovarian (corpus luteum) hemorrhage during anticoagulation therapy. (ijrcog.org)
  • Gupta N, Dadhwal V, Deka D, Jain SK, Mittal S. Corpus luteum hemorrhage: rare complication of congenital and acquired coagulation abnormalities. (ijrcog.org)
  • Murao H, Kinjyo, K. Demura T. Conservative therapy for corpus luteum hemorrhage, a review of 116 cases. (ijrcog.org)
  • Changes in expression of vascular endothelial growth factor and angiopoietin-1 and -2 in the macaque corpus luteum during the menstrual cycle. (oregonstate.edu)
  • These data suggest transcriptional control of VEGF, Ang-1 and Ang-2, as well as post-transcriptional control of VEGF, in macaque corpus luteum. (oregonstate.edu)
  • A new corpus luteum develops with each menstrual cycle. (wikipedia.org)
  • Our previous flow cytometry results demonstrated a significant increase in neutrophils, macrophages/monocytes, and natural killer (NK) cells in dispersed rhesus monkey corpora lutea (CL) after progesterone (P4) levels had fallen below 0.3 ng/ml for ≥3 days during the natural menstrual cycle. (bioone.org)
  • As the lining of the womb is no longer maintained by progesterone from the corpus luteum, the lining breaks away, resulting in menstrual bleeding. (medicalnewstoday.com)
  • In the ovarian cycle, repeated patterns of specific cellular proliferation, differentiation, and transformation occur that accompany the process of follicular development and the formation and function of the corpus luteum [ 2 ] . (encyclopedia.pub)
  • Endothelial cells communicate with cells comprising the functional unit of the corpus luteum, i.e ., other vascular cells, steroidogenic cells, and immune cells. (biomedcentral.com)
  • During the bovine estrous cycle, plasma levels of progesterone increase in parallel to the levels of P450scc and its electron donor adrenodoxin, indicating that progesterone secretion is a result of enhanced expression of P450scc in the corpus luteum. (wikipedia.org)
  • The specific aims of the proposed research are to purify and further characterize this new protein kinase and evaluate its physiological significance in rat and bovine corpora lutea. (nebraska.edu)
  • Townson, D.H. Immune cell-endothelial cell interactions in the bovine corpus luteum. (unh.edu)
  • It then degenerates into a corpus albicans, which is a mass of fibrous scar tissue. (wikipedia.org)
  • Although many of the effects of luteinizing hormone (LH) in the corpus luteum are thought to be mediated by cAMP, the exact mechanism of action of LH is unknown. (nebraska.edu)
  • The size of the corpus luteum depends on the ovarian activity (Musa and Abusinea, 1978). (fao.org)
  • Patients on anticoagulant therapy can rarely present with life threatening haemoperitoneum, secondary to ruptured corpus luteum Early diagnosis and reversal of anticoagulation can be lifesaving in this condition which carries significant mortality Unlike ruptured ectopic, ruptured corpus luteum causing haemoperitoneum due to warfarin induced coagulopathy can be managed conservatively, as bleeding stops after reversal of anticoagulation. (ijrcog.org)
  • Anestrus in conjunction with a persistent corpus luteum probably reflects some interference with normal function of the uterine endometrium. (drugs.com)
  • The corpus luteum produces oestrogen and progesterone which change the secretory endometrium into decidua. (gfmer.ch)
  • The corpus luteum was larger and lasted longer when mating occurred at the time of maximum follicular development. (fao.org)
  • The [very fancy sounding] corpus luteum produces progesterone. (yahoo.com)
  • Following implantation, the trophoblast produces hCG which maintains the corpus luteum. (gfmer.ch)
  • If fertilization does not occur, the corpus luteum breaks down, less progesterone is produced, and the levels of progesterone are too low to promote the growth of the uterine wall. (medicalnewstoday.com)
  • The placenta begins to secrete progesterone to supplement, and surpass, the progesterone already secreted by the corpus luteum. (medicalnewstoday.com)
  • It is doubtful that corpora lutea are retained indefinitely in cattle with normal uterine function. (drugs.com)
  • In order to test for this hypothesis the present work deals with the determination of progesterone and estrogene receptors during the courseof diestrus in corpora lutea of non-pregnant bitches. (uni-giessen.de)
  • Recently, we focused on the role of RAS protein in the ovarian corpus luteum. (encyclopedia.pub)
  • Burbach, J. A. / Localization of lipid peroxidation-derived protein epitopes in the porcine corpus luteum . (johnshopkins.edu)
  • The development of the corpus luteum is accompanied by an increase in the level of the steroidogenic enzyme P450scc that converts cholesterol to pregnenolone in the mitochondria. (wikipedia.org)
  • Prolonged maintenance of the corpus luteum has also occurred following hysterectomy or experimental induction of endometritis. (drugs.com)
  • Analogous to events occurring in the corpus luteum, the vascular endothelium of other tissues responds to extracellular signals during the physiologic processes of embryonic development and wound healing, and in the pathologic process of tumor angiogenesis. (biomedcentral.com)
  • Spontaneous haemoperitoneum (SH) due to bleeding corpus luteum secondary to warfarin induced coagulopathy is encountered very rarely. (ijrcog.org)
  • Da eine solche Wirkung an die Expression spezifischer Rezeptoren gebunden ist, war es Ziel vorliegender Arbeit im Hinblick einerVerifizierung der aufgestellten These, die Expression von Progesteron- und Östrogenrezeptoren im Verlauf des Diöstrus im Corpus luteumingravider Hündinnen zu erfassen. (uni-giessen.de)
  • However, the function of RAS in the ovarian corpus luteum is not clear. (encyclopedia.pub)
  • New blood vessel growth is essential for the formation and function of the corpus luteum. (biomedcentral.com)
  • The regulation of phosphoinositide metabolism by LH and other hormones and the presence of C-kinase in the corpus luteum suggest that the control of C-kinase activity is related to the function of the corpus luteum. (nebraska.edu)
  • The proposed studies on the ovarian C-kinase may provide new insight into the mechanism of LH action and establish a link between hormonally-induced changes in C-kinase activation and corpus luteum function. (nebraska.edu)
  • abstract = "Reactive oxygen species (ROS) generated within the corpus luteum (CL) are believed to play an integral role in luteolysis. (johnshopkins.edu)
  • citation needed] If the egg is not fertilised, the corpus luteum stops secreting progesterone and decays (after approximately 10 days in humans). (wikipedia.org)
  • Apparently to cope with the radicals produced by this system and by enhanced mitochondrial metabolism, the levels of antioxidant enzymes catalase and superoxide dismutase also increase in parallel with the enhanced steroidogenesis in the corpus luteum. (wikipedia.org)