Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00627 (MAP)
 15,705 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The metabolism of pregnenolone-4-14C of ovaries from human foetuses ranging in age from the 14th through the 42th week of gestation was studied by a double isotope method in vitro. Progesterone was found as the main metabolite. The rate of conversion is correlated with histochemical findings of the same material and comparison with the FSH- and LH-concentration in human foetal pituitaries is made. As further metabolites only 17alpha-hydroxypregnenolone and dehydroepiandrosterone were isolated. For comparison tissue from a polycystic ovary was investigated with the same method.
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PMID:Steroid metabolism of foetal tissues. I. Metabolism of pregnenolone-4-14C by human foetal ovaries. 12 47

Estradiol-benzoate (EB) injected into previously ovariectomized (OVX) rats, increased pituitary ATPase activity 69% over controls, within one hour of treatment. Twelve hours after injection, ATPase activity was not significantly different from controls. Progesterone [(P): 5mg/100gBW] administered in conjunction with EB elicited an analogous response. AT at time of EB and EB+P induced increments in pituitary ATPase activity, plasma LH levels were dramatically reduced to normal, intact diestrous control levels. Post-castrational elevations in FSH were also suppressed after one hour of treatment with EB, but not following EB+P administration. The results suggest that the inhibitory actions of EB and EB+P on post-castrational LH levels may be related to modulation by these steroids of pituitary membrane ATPase activity.
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PMID:Estrogen (EB) and EB + progesterone (P) induced changes in pituitary sodium, potassium adenosine triphosphatase activity (ATPase). 13 41

Although sex steroids were known to play a role in the control of LH, FSH, TSH and prolactin secretion, in vivo experiments could not discriminate between hypothalamic and pituitary sites of action. In this study, the specific action of sex steroids at the anterior pituitary level could be achieved using rat adenohypophyseal cells in primary culture. While estrogens stimulated the sensitivity of the LH and FSH responses to LHRH, androgens had differential effects on the secretion of the two gonadotropins: marked inhibition of LH and stimulation of FSH secretion. Progesterone, on the other hand, while having no effect in the absence of estrogens, could reverse the stimulatory effect of estrogens on LH release while it led to a stimulation of FSH secretion. Estrogens and thyroid hormone exert respective stimulatory and inhibitory effects on TSH secretion by a direct action at the pituitary level. These effects appear to be mediated changes of the level of adenohy-pophyseal TRH receptors. A close correlation was observed between the specificity of binding of the dopamine agonist (3H)dihydroergocryptine and the control of prolactin release in cells in culture, thus supporting the physiological importance of the dopamine receptor in the control of prolactin release. The high degree precision of this system permits assessment of activity of not only dopamine agonists and antagonists, but also of compounds having mixed agonist-antagonistic activity. Preincubation of anterior pituitary cells with 17beta-estradiol not only stimulated basal and TRH-induced prolactin release but, more unexpectedly, led to an almost complete reversal of the inhibitory effect of dopamine agonists on prolactin secretion. Besides its own interest, the adenohypophyseal cell culture system could well be used as a model system for study of the interaction between estrogens and dopaminergic action.
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PMID:[Specific role of sex steroids on the pituitary level. Sex steroids and anterior pituitary secretion]. 20 92

The present study was undertaken to identify the hypothalamic locus where norepinephrine (NE) nerve terminals communicate with luteinizing hormone-releasing hormone (LH-RH)-containing neurons involved in the stimulatory feedback action of gonadal steroids on LH and FSH release. Ovariectomized rats received estradiol benzoate (10 microgram/rat s.c.) on day 0. Intracranial implants containing either 6-hydroxydopamine (6-OHDA), to destroy NE terminals, or cocoa butter (controls) were placed bilaterally in the suprachiasmatic nucleus (SCN), medial basal hypothalamus (MBH) or olfactory tubercle (OT) on day 1. Progesterone (P, 5 mg/rat s.c.) was administered at 10.00 h on day 2 to elicit increases in serum LH and FSH and the MBH LH-RH levels in the afternoon. Implantation of 6-OHDA in the SCN resulted in a marked depletion of NE in and around the region of the SCN in the preoptic-anterior hypothalamic area (POA-AH) without adversely affecting dopamine (DA) concentrations, and blocked the P-induced afternoon increase in the MBH LH-RH and serum gonadotropin levels. Similar reduction in the MBH NE concentrations occurred following placement of 6-OHDA in the MBH; however, these as well as implants in the OT were ineffective in suppressing the P-induced effects. These studies show that functional integrity of the SCN regions is critical in manifestation of the P-induced rise in the MBH LH-RH activity, and this region in the POA-AH, therefore, may be the primary locus of synaptic communication between NE terminals and LH-RH neurons.
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PMID:Blockade of progesterone-induced increase in hypothalamic luteinizing hormone-releasing hormone levels and serum gonadotropins by intrahypothalamic implantation of 6-hydroxydopamine. 22 26

Pituitary LH and FSH repsonses to synthetic LHRH as estimated by increases in plasma FSH and LH 15 and 45 min following its iv injection were enhanced during the first 2 weeks of life, reaching a maximum around day 10-15 and declining thereafter. No AM.-PM. variations in pituitary responsiveness were observed at any age studied. The increased pituitary response found in infantile rats did not appear to be caused by a slower rate of disappearance of LHRH in blood of the younger animals. Ovariectomy-adrenalectomy. (Ovx-Adrx) or Ovx at day 10, but not Adrx alone, resulted in elevated LH and FSH levels 5 days later and almost complete obliteration of the FSH response to LHRH. The LH response was not altered. Treatment with 5alha-dihydrotestosterone (DHT) but not with estradiol benzoate (EB) or testosterone propionate (TP) suppressed the post-Ovx-Adrx rise in plasma LH and FSH. Progesterone (P) potentiated the effect of DHT. Restoration of basal plasma LH and FSH levels (by DHT and/or P) restored FSH responsiveness to exogenous LHRH. EB and TP were ineffective. The LH response was slightly depressed by EB + DHT. It is concluded that the elevated plasma FSH levels in the infantile female rat may be due at least in part to a high degree of pituitary responsiveness to LHRH and/or FSH-RF brought about by steroidal signal of ovarian origin. DHT and P appear to be the steroids responsible for such a stimulatory action.
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PMID:Developmental changes in pituitary responsiveness to luteinizing hormone-releasing hormone (LHRH) in the female rat: ovarian-adrenal influence during the infantile period. 31 94

Nineteen Scottish Blackface ewes were given LH-RH (3 X 30 micrograms i.v., 90-min intervals) during anoestrus when prolactin levels were elevated. Plasma levels of prolactin were suppressed with CB 154 (twice daily, i.m.) on Days -5 to 0 (N = 5), 0 to +5 (N = 5) or -5 to +5 (N = 5) around the day of LH-RH treatment (Day 0). Control animals (N = 4) received saline on Days -5 to +5. Nine animals ovulated forming corpora lutea as judged by laparoscopy on Day +7. No difference in FSH or LH levels was found between treatments and ovulations occurred equally in all treatment groups. Progesterone levels were less than ng/ml in all animals up to Day 14. It is concluded that short-term suppression of prolactin does not affect the incidence of ovulation or corpus luteum progesterone production in LH-RH-treated anoestrous ewes.
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PMID:Effect of suppression of plasma prolactin on ovulation, plasma gonadotrophins and corpus luteum function in LH-RH-treated anoestrous ewes. 38 78

Deeply acyclic (seasonally anovulatory) mares were treated with GnRH or a GnRH analogue to induce follicular development and ovulation. Courses of GnRH (3--4) were administered at approximately 10-day intervals to reproduce the gonadotrophin surges which precede ovulation in the normal cycle. Exogenous progesterone was administered in an attempt to reproduce the luteal phase pattern. Induced serum FSH concentrations were comparable to those causing follicular development in the normal cycle, but induced LH levels were lower and of shorter duration than those of the periovulatory surge. Three of 4 mares treated with GnRH appeared to ovulate, but did not establish CL. Nine of 10 mares given GnRH analogue also developed follicles during the final treatment course, as did mares treated with progesterone only, while only 1 of 5 untreated control mares showed any ovarian development. Failure to induce final follicular maturation and CL development by this treatment regimen may be due to an inadequate LH surge at the time of the expected ovulation associated with the low preovulatory oestradiol-17 beta surge, possibly caused by the preceding FSH stimulation being inadequate or inappropriate. Progesterone treatment increased baseline FSH concentrations in GnRH-treated mares, and also stimulated follicular development in mares not treated with GnRH, indicating a possible role for progesterone in folliculogenesis and, indirectly, ovulation.
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PMID:Induction of follicular development and ovulation in seasonally acyclic mares using gonadotrophin-releasing hormones and progesterone. 38 82

The assessment of the hormonal cycle after hysterectomy by means of radioimmunological determination of FSH, LH, Progesterone and Estradiol-17beta in serum and BBT-measurement revealed no obvious difference to a corresponding control-group of preclimacteric and climacteric women. The vegetative climacteric syndrome is much more frequently connected with the stable hypergonadotropic type than with the fluctuating hypergonadotropic or normogonadotropic type. Within the last two groups there is no correlation between vegetative complaints and the exent of ovarian function.
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PMID:[Ovarian function and vegetative complaints after hysterectomy in normally cycling women (author's transl)]. 43 65

Gonadotropin-releasing hormone (GnRH) was administered to 141 women, 15-22 years of age, who were using various oral contraceptive (o.c.) preparations. LH, FSH, Progesterone, and estradiol levels, as well as LH and FSH stimulation rates, were measured before and after o.c. use. The women were divided into 4 groups: I: 50 mcg ethinyl estradiol (EE) and 1 mg lynestrol (L); II: 50 mcg EE and .75 mg L; III: 37.5 mcg EE and .75 mg L; IV: .5 mg L. In group I, all values were significantly lowered, and there was a significant decrease in LH and FSH stimulation rates (p ? .001). In group II, the same results were obtained, except that the pre-GmRH levels approached values observed before o.c. use with increased length of o.c. use. In group III, all values tended to return to the pre-o.c. levels as the o.c. use progressed. In group IV, only progesterone levels and LH stimulation rates were significantly reduced. Low-dosage combination preparations should be administered to adolescents with stable cycles, and mini-pills to those who haven't established regular cycles.
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PMID:[Comparative biochemical investigations with contraceptives at different dose levels (author's transl)]. 46 47

Male (1--60 days old) and female (1--30 days old) hamsters were decapitated and serum levels of LH, FSH, PRL, progesterone, androgens (males), and estradiol (females) were measured by RIA. Males and females had similar levels of LH until 15 days of age and of FSH until 12 days of age, at which times gonadotropin levels increased significantly in females. Peak levels for females occurred on days 19--21 for LH and on days -2--24 for FSH, later than the times reported for female rats. Adjusting female gonadotropin peaks for gestation length places these peaks for hamsters and rats at the same time in postmating age. In female hamsters, large variations occur in LH between 16--25 days of age, as reported for female rats. Males reached peak serum levels of LH and FSH on day 40, just before the first motile epididymal sperm. Serum PRL levels were identical in male and female hamsters until at least day 30. PRL levels sharply increased in both sexes after day 18 and remained elevated until at least day 30. In males, serum androgens were low until 30 days of age, in contrast to high levels reported for infantile rats. Androgens rose sharply in male hamsters after day 30 to peak levels on day 50. Progesterone in males also remained low until after day 30. Serum estradiol in females did not attain the extremely high elevations seen in rats. Some fluctuations occurred between 10--30 days of age, which presumably represent maturational changes in the ovary. Serum progesterone in females followed a pattern of development similar to estradiol.
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PMID:The development of gonadotropin and steroid hormone patterns in male and female hamsters from birth to puberty. 47 8


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