• GnRH
  • Pulsatile administration of gonadorelin (GnRH) by subcutaneous (SC) or preferably intravenous (IV) infusion restores pituitary-gonadal axis function and fertility in the majority of people with Kallmann syndrome and idiopathic hypogonadotropic hypogonadism. (medscape.com)
  • This subpopulation is targeted by a large number of steroid hormones and works to form a network that feeds back to GnRH pulse generator. (wikipedia.org)
  • Five exon segments in the TAC3 gene encode for the NKB precursor known as preprotachykinin B. Preprotachykinin B is then proteolytically cleaved into the pro-peptide proneurokinin B. A second proteolytic cleavage of proneurokinin B produces the final product neurokinin B. During the ovarian cycle, GnRH secretion along with that of luteinizing hormone (LH) is highly regulated. (wikipedia.org)
  • Leuprorelin and goserelin are GnRH analogs which are used primarily for the treatment of hormone-responsive prostate cancer. (wikipedia.org)
  • Because the initial endocrine response to GnRH analogs is actually hypersecretion of gonadal steroids, hormone receptor antagonists such as flutamide are typically used to prevent a transient boost in tumor growth. (wikipedia.org)
  • Some neurochemicals and peripheral hormones [e.g.gamma-aminobutyric acid (GABA), opiates, gonadal sex steroids, inhibin] can modulate gonadotropin release, but GnRH was considered to have no hypothalamic antagonist. (wikipedia.org)
  • progesterone
  • Estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, sex hormone-binding globulin, F(2)-isoprostanes, and thiobarbituric acid-reactive substances were measured up to 8 times per cycle at clinic visits timed by using fertility monitors. (biomedsearch.com)
  • however, OCPs less closely mimic the physiologic menstrual cycle and thus are inferior to true hormone replacement therapy (eg, transdermal estradiol plus cyclic progesterone, see below). (medscape.com)
  • Physiologic hormone replacement therapy (HRT) most closely mimics the natural menstrual cycle by replacing (1) adequate levels of estradiol to maintain bone health and prevent symptoms of hypoestrogenemia (hot flashes, vaginal dryness, decreased libido) and (2) cyclic progesterone to induce withdrawal bleeding and thereby protect the endometrium in uterus-intact women. (medscape.com)
  • glycoprotein hormones
  • The protein dimer contains 2 glycopeptidic subunits, labeled alpha and beta subunits, that are non-covalently associated (i.e., without any disulfide bridge linking them): The alpha subunits of LH, FSH, TSH, and hCG are identical, and contain 92 amino acids in human but 96 amino acids in almost all other vertebrate species (glycoprotein hormones do not exist in invertebrates). (wikipedia.org)
  • behavior
  • Anosmic males were less vigorous and persistent in their courtship, suggesting that, either a female pheromone and/or high levels of hormone are necessary to maintain full reproductive behavior in male kokanee. (biomedsearch.com)
  • The role of socially induced hormone changes in modulating reproductive behavior is discussed. (biomedsearch.com)
  • His research has focused on the cellular processes behind how brain function and behavior are modified by steroid hormones, and his papers have covered topics such sex differences in the brain, the effects of hormones on rodent brains and behavior, and the effects of steroid hormones on social behavior. (wikipedia.org)
  • These three forms influence neuronal excitability, but very little is known about their inter-hormone interactions, the relative concentrations and ratios of E1/E2/E3 and how that may influence the seizure frequency behavior in women with epilepsy. (wikipedia.org)
  • Prenatal factors that affect or interfere with the interaction of these hormones on the developing brain can influence later sex-typed behavior in children. (wikipedia.org)
  • However, few of these have been related to behavioral sex differences, and scientists are still working to establish firm links between early hormones, brain development and behavior. (wikipedia.org)
  • estrogens
  • Other contexts will include progestogens as a third class of sex steroids, distinct from androgens and estrogens. (wikipedia.org)
  • In general, androgens are considered "male sex hormones", since they have masculinizing effects, while estrogens and progestogens are considered "female sex hormones" although all types are present in each sex, albeit at different levels. (wikipedia.org)
  • Through many animal models, as well as human-use of estrogen-based hormone replacement therapy, estrogens have been seen to increase the excitability of neurons, leading to a decreased seizure threshold. (wikipedia.org)
  • Two of the most significant differences between puberty in girls and puberty in boys are the age at which it begins, and the major sex steroids involved, the testosterones and the estrogens. (wikipedia.org)
  • Spermatogenesis
  • In birds and mammals, luteinizinghormone (LH) regulates sex steroid production as well as ovulation, whereas follicle stimulating hormone (FSH) promotes spermatogenesis and ovarian follicle maturation. (wikipedia.org)
  • certain hormones
  • Because steroid hormones are powerful drivers of gene expression in certain cancer cells, changing the levels or activity of certain hormones can cause certain cancers to cease growing, or even undergo cell death. (wikipedia.org)
  • The hormonal theory of sexuality holds that, just as exposure to certain hormones plays a role in fetal sex differentiation, such exposure also influences the sexual orientation that emerges later in the adult. (wikipedia.org)
  • anabolic steroids
  • Synthetic androgens are often referred to as anabolic steroids. (wikipedia.org)
  • Since their discovery, anabolic steroids (AAS) have been widely used as performance-enhancing drugs to improve performance in sports, to improve one's physical appearance, as self-medication to recover from injury, and as an anti-aging aid. (wikipedia.org)
  • Use of anabolic steroids for purposes other than treating medical conditions is controversial and, in some cases, illegal. (wikipedia.org)
  • Major sports organizations have moved to ban the use of anabolic steroids. (wikipedia.org)
  • It was not until the 1950s, however, that athletes began to discover that anabolic steroids could increase their muscle mass. (wikipedia.org)
  • Throughout the 1960s and 1970s, the use of anabolic steroids was confined largely to the professional levels of sport. (wikipedia.org)
  • In the Eastern bloc, programs of training went as far as forcing some athletes to take anabolic steroids. (wikipedia.org)
  • In the United States, sports physicians, including Ziegler, and medical texts were still widely proclaiming that anabolic steroids were ineffective in helping athletes gain muscle. (wikipedia.org)
  • These doctors did acknowledge the usefulness of anabolic steroids for debilitated patients. (wikipedia.org)
  • The package insert for Dianabol, a common anabolic steroid used at the time, stated, "Anabolic steroids do not enhance athletic ability. (wikipedia.org)
  • Despite these warnings, use of anabolic steroids began in competition bodybuilding, in track and field events, such as the shot put, and in other sports where performance depended on muscle strength or speed of recovery during training. (wikipedia.org)
  • This open label study, conducted by J.P. O'Shea and colleagues at Oregon State University, confirmed the muscle building effects of anabolic steroids on athletes that followed a high protein diet. (wikipedia.org)
  • At the beginning of the 1970s, sporting organizations, including the IOC and NCAA, declared the use of anabolic steroids unethical, but with no effective means of testing athletes, the issue remained academic. (wikipedia.org)
  • It is difficult to determine what percent of the population have used anabolic steroids due to the fact that most studies are based on self-reporting. (wikipedia.org)
  • About 13% reported unsafe injection practices such as reusing needles, sharing needles, and sharing multi-dose vials, though a 2007 study found sharing of needles was extremely uncommon (less than 1%) among individuals using anabolic steroids for non-medical purposes. (wikipedia.org)
  • The same study found that individuals using anabolic steroids for non-medical purposes had a higher employment rate and a higher household income than the general population. (wikipedia.org)
  • endocrine
  • A marked reduction in milt and plasma hormones following cauterization of the olfactory nares indicates that olfactory stimuli play a role in mediating endocrine and spermiation responses to the nesting females. (biomedsearch.com)
  • It involves the manipulation of the endocrine system through exogenous or external administration of specific hormones, particularly steroid hormones, or drugs which inhibit the production or activity of such hormones (hormone antagonists). (wikipedia.org)
  • FS cells form homologous gap junctions with their adjacent counterparts, but also heterologous gap junctions with hormone-secreting endocrine cells. (wikipedia.org)
  • neuronal
  • Neuroendocrine cells are cells that receive neuronal input (neurotransmitters released by nerve cells or neurosecretory cells) and, as a consequence of this input, release message molecules (hormones) to the blood. (wikipedia.org)
  • The adrenal medullary hormones are kept in vesicles much in the same way neurotransmitters are kept in neuronal vesicles. (wikipedia.org)
  • Growth hormone is secreted in pulses, which arise from alternating episodes of GHRH release and somatostatin release, which may reflect neuronal interactions between the GHRH and somatostatin cells, and negative feedback from growth hormone. (wikipedia.org)
  • reproductive
  • Influence of endogenous reproductive hormones on F2-isoprostane levels in premenopausal women: the BioCycle Study. (biomedsearch.com)
  • Endogenous reproductive hormones and oxidative stress have been independently linked to risk of chronic disease but mostly in postmenopausal women. (biomedsearch.com)
  • The interplay between endogenous reproductive hormones and oxidative stress among premenopausal women, however, has yet to be clearly elucidated. (biomedsearch.com)
  • The objective of this study was to investigate the association between endogenous reproductive hormones and F(2)-isoprostanes in the BioCycle Study. (biomedsearch.com)
  • regulate
  • The study of fibronectin expression in these cells suggests that FS cells may help regulate pituitary function, by interacting with hormone secreting cells through fibronectin. (wikipedia.org)
  • hormonal
  • List of investigational hormonal agents Sexual motivation and hormones Guerriero, G (April 2009). (wikipedia.org)
  • Hormonal therapy in oncology is hormone therapy for cancer and is one of the major modalities of medical oncology (pharmacotherapy for cancer), others being cytotoxic chemotherapy and targeted therapy (biotherapeutics). (wikipedia.org)
  • effects
  • Therefore, the present study provided further support for the organizational and activational effects of gonadal steroid hormones but it also has shown that social environments have an active role in the expression of sexually differentiated behavioral patterns. (usc.edu)
  • Steroid effects were independent of both LHRH pulse amplitude and frequency. (semanticscholar.org)
  • Cortisol is a major stress hormone and has effects on many tissues in the body, including the brain. (wikipedia.org)
  • posterior
  • In addition to axons, the posterior pituitary also contains pituicytes, specialized glial cells resembling astrocytes assisting in the storage and release of the hormones. (wikipedia.org)
  • apoptosis
  • When the action of aromatase is blocked, estrogen levels in post-menopausal women can drop to extremely low levels, causing growth arrest and/or apoptosis of hormone-responsive cancer cells. (wikipedia.org)
  • adolescents
  • The activation of steroid hormones experienced by adolescents had an obvious effect on sexually dimorphic behaviors observed in adolescent males and females. (usc.edu)
  • levels
  • However, both male and female hormone levels remained relatively stable. (usc.edu)
  • This study examines the relationship between social status, behavioral activity, and hormone levels through the spawning cycle in male kokanee salmon (Oncorhynchus nerka). (biomedsearch.com)
  • After transplantation, patients receive ultrasound monitoring together with measurement of serum hormone levels for 10-12 months. (stanford.edu)
  • If pregnancy occurs, LH levels will decrease, and luteal function will instead be maintained by the action of hCG (human chorionic gonadotropin), a hormone very similar to LH but secreted from the new placenta. (wikipedia.org)
  • mechanisms
  • These results help to elucidate the mechanisms underlying steroid feedback in vivo, since reduction in pituitary responsiveness to LHRH may play an important role in T feedback, while facilitation by E of both self-priming and desensitization may serve to increase the magnitude and shorten the duration of the proestrous LH surge. (semanticscholar.org)
  • Mechanisms of sex hormone action. (semanticscholar.org)
  • Influential
  • Estrone is the major estrogen after menopause, and this hormone may be very influential in seizure control of the catamenial woman if she is severely overweight or obese. (wikipedia.org)