Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because TRH counteracts the inhibitory effect of opiate peptides on LH secretion in cultured cells from normal pituitaries, six normal postmenopausal women were studied to determine whether TRH interacts in vivo with opioid peptides in the regulation of pituitary hormone secretion. At two different times a constant 3 h infusion of either saline or TRH (5 micrograms/min) was initiated. At 60 min a 250 micrograms bolus of the opiate agonist peptide D-Ala2-MePhe4-met-enkephalin-0-ol (DAMME) was injected in one of the two saline and TRH infusion tests. The four treatments, i.e. saline infusion alone, saline infusion with a DAMME bolus, TRH infusion alone; and TRH infusion with DAMME bolus were given at random with an interval of at least 7 d. Blood samples were taken every 15 min during the 3 h study. DAMME induced a significant fall (P less than 0.05) in serum LH (from 35 +/- 8.5 to 18.3 +/- 5.1 mIU/ml) (mean +/- SEM) without significantly affecting FSH levels (from 29 +/- 11.2 to 26.9 +/- 12.4 mIU/ml). These changes were not antagonized by the continuous infusion of TRH. PRL had a monophasic response pattern to continuous isolated TRH infusion; the basal levels increased from 4.2 +/- 1.2 to 24.5 +/- 6.8 ng/ml at 30 min and then slowly decreased with a plateau from 90 min until the end of the study. DAMME administration at 60 min induced a significant second peak of PRL secretion (44 +/- 6.5 ng/ml) 30 min later (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Interaction of thyrotrophin releasing hormone and the enkephalin analogue DAMME on pituitary hormone secretion. 311 78

FSH bioactivity was measured by means of FSH-dependent aromatase activity (conversion of androgen substrate to estradiol). Assay sensitivity was optimized by the use of immature (7-10 days old) rats as Sertoli cell donors, serum-free medium for incubation, phosphodiesterase inhibitor (methylisobutylxanthinine), serial dilution of FSH in medium containing 1% BSA, delayed addition of FSH for 72 h after cell plating, and 19-hydroxyandrostenedione (2.5 X 10(-6) M) as the aromatizable androgen substrate. The method consisted of subjecting the decapsulated immature rat testes to a 2-step collagenase dispersion, plating the cells in medium [Dulbecco's Modified Eagle's Medium-Ham's F-10 (1:1)] containing growth factors and methylisobutylxanthinine for 72 h, adding increasing doses of FSH to the standard curve or small volumes of serum to the test vials as well as 19-hydroxyandrostenedione for 24 h, and measuring estradiol by RIA in dilutions of the medium. Using NIAMDD human (h) FSH-2 as the bioassay standard, the useful range of the assay was 0.01-5.0 ng/ml. Specificity was determined by the addition of graded doses of hLH, hTSH, ACTH, hGH, hPRL, and hCG. The minor degree of FSH bioactivity observed in a few hormone preparations was accounted for by the degree of FSH contamination in them. Mean intra- and interassay coefficients of variation were 9% and 11%, and the index of precision was 0.049. This bioassay was used to determine the bioactive FSH content of pituitary extracts, tissue culture media, elutions from columns, and isoelectrically focused samples. More importantly, small quantities of human sera gave responses parallel to the standard curve in a minimum of two dilutions. The bio- to immunoreactive ratios, expressed as the mean +/- SEM (NIAMDD-hFSH-2), were 0.66 +/- 0.2 in boys (n = 6), 0.78 +/- 0.2 in pubertal girls (n = 6), 1.18 +/- 0.2 in men (n = 13), 1.24 +/- 0.1 in postmenopausal women (n = 30), 1.94 +/- 0.3 in the follicular phase (n = 19), 6.2 +/- 1.4 in the ovulatory phase (n = 19), and 1.6 +/- 0.4 in the luteal phase (n = 19) of the normal menstrual cycle. These results indicate that the bio- to immunoreactive hFSH ratio in the circulation, is dependent upon the hormonal milieu of the subject.
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PMID:An improved in vitro bioassay for follicle-stimulating hormone (FSH): suitable for measurement of FSH in unextracted human serum. 311 17

The effect of pulsatile administration of 'pure' FSH on the endogenous LH surge was investigated in 10 infertile but otherwise normal women. In each woman the LH surge in the spontaneous cycle preceding the treatment cycle was characterized in blood samples taken every 6 h. FSH was injected s.c. via a pump (28 IU every 3 h) starting on cycle day 2. Only five of the FSH-treated women displayed an endogenous LH surge, and this was markedly attenuated in four of them. The LH surge occurred significantly earlier in the FSH-treated than in the corresponding spontaneous cycle (cycle day 10.2 +/- 0.5 vs 13.6 +/- 0.8 mean- +/- SEM, P less than 0.05), although it tended to occur later in the FSH-treated cycles with a higher total follicular fluid volume of follicles 12-15 mm in diameter. This volume was even greater in the FSH-treated cycles without an endogenous LH surge. Serum progesterone levels increased significantly in all five FSH-treated cycles after the onset of the LH surge and ovulation was confirmed by ultrasound in four of them. These results suggest that the LH surge during superovulation induction with pulsatile FSH in normally cycling women is a variable event. We postulate that unknown inhibitory substances secreted be small growing follicles antagonize the positive feedback effect of E2 on LH secretion.
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PMID:The effect of pulsatile follicle stimulating hormone on the endogenous luteinizing hormone surge in women. 311 29

To appraise the physiological pattern(s) of episodic testosterone and FSH release in man, we withdrew blood samples at 10-min intervals for 24-36 h in a total of 15 normal men. We subjected the resulting FSH (15 men) and testosterone (5 men) time series to 3 statistically based and mathematically independent procedures for detecting hormone pulsatility, viz. Cluster analysis, the Detect program, and Fourier transformation. The Cluster technique disclosed discrete testosterone and FSH peaks occurring at mean (+/- SEM) interpulse intervals of 112 +/- 14 and 85 +/- 3.4 min, respectively. These values were not significantly different from the mean LH interpulse interval of 95 +/- 11 min. The average durations of the testosterone and FSH pulsations were 90 +/- 11 and 59 +/- 3 min, respectively. The mean testosterone pulse amplitude reached a maximal value of 910 +/- 92 ng/dL (31.5 +/- 3.2 nmol/L), which represented a mean increase of 242 +/- 26 ng/dL (8.4 +/- 0.9 nmol/L) above the preceding nadir. FSH pulses had a maximum of 7.2 +/- 0.3 IU/L, and an incremental amplitude of 1.3 +/- 0.1 IU/L. An independent pulse detection procedure. Detect, yielded a testosterone pulse frequency of 12.3 +/- 0.8 pulses/day [P = NS vs. Cluster program (13 +/- 1.9 pulses/day)]. The Cluster and Detect estimates of FSH pulse frequency were also similar, viz. 16 +/- 1.9 and 16 +/- 0.6 pulses/day. Further analysis by Fourier transformation revealed significant circadian periodicities for serum testosterone, FSH, and LH, which had mean nyctohemeral amplitudes of 185 ng/dL (6.4 nmol/L), 0.38 IU/L, and 1.3 IU/L, respectively. Cross-correlation analyses disclosed significantly positive uncorrected cross-correlations between LH and testosterone that were maximal at a testosterone lag of 60 min (range, 50-70 min). To eliminate high intrinsic autocorrelations within the testosterone and LH time series, stepwise autoregressive fitting was employed. The resulting partial cross-correlation matrices indicated that LH concentrations at any given instant were significantly positively correlated to testosterone concentrations lagged by 10 and 20 min. Similarly, contemporaneous LH and FSH concentrations were significantly positively correlated (r = 0.40-0.89; P less than 0.001). Moreover, autoregressive modeling disclosed significantly positive partial cross-correlations between LH and FSH at a FSH lag of 10 min. In summary, we have identified significant pulsatile as well as circadian (24-h) patterns of testosterone and FSH release in normal men.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Operating characteristics of the male hypothalamo-pituitary-gonadal axis: pulsatile release of testosterone and follicle-stimulating hormone and their temporal coupling with luteinizing hormone. 311 34

Epidermal growth factor (EGF) stimulates granulosa cell (GC) proliferation of certain species and modulates FSH-induced GC differentiation. The present study was undertaken to characterize the binding properties of the EGF receptor in porcine GCs to determine if the EGF responsiveness of mitotically active porcine GCs was related to their differentiated state and was regulated by reproductive hormones in vitro. Characterization of the EGF receptor-binding properties of porcine GCs revealed that saturation binding was achieved with 10 ng/ml [125I]iodo-EGF after 1 h at 37 C. In all states of differentiation, porcine GCs expressed few (less than 20,000/cell), specific, high affinity EGF receptors with apparent Kd values of 5.5 +/- 0.7 X 10(-10) M (mean +/- SEM; n = 6). Freshly harvested GCs obtained from small follicles were considered slightly differentiated (SDs) and bound, on the average, 2.6-fold more [125I]iodo-EGF than highly differentiated cells (HDs) obtained from large follicles which had further differentiated in vivo. The difference in binding was due to a decrease in receptor number and not to a change in receptor affinity. This relationship observed in freshly harvested cells was maintained in culture for a limited period. At 48 h of culture, the [125I]iodo-EGF-binding capacity of SDs was higher than that of HDs and was inversely related to the state of differentiation, as measured by [125I]iodo-LH/hCG-binding capacity. After 96 h, however, the EGF-binding capacity of HDs increased 3.7-fold from the level of binding at 48 h, while the LH/hCG-binding capacity decreased 10-fold. Conversely, the EGF-binding capacity of SDs decreased 28%, while the LH/hCG-binding capacity remained low. These experiments indicated that the state of GC differentiation was inversely correlated with EGF receptor number and that this relationship was not maintained in culture beyond 48 h. FSH treatment within the first 48 h of culture decreased the EGF-binding capacity of SDs 35% relative to the control value, but estradiol and dihydrotestosterone had no effect. FSH also regulated the mitotic responsiveness to EGF. EGF treatment of cultured SDs stimulated an 84% increase in cell number and a 178% increase in [3H]thymidine incorporation. These effects were suppressed by a high concentration of FSH. Thus, the ability of porcine GCs to bind EGF was changed with differentiation in vivo, while both EGF-binding capacity and mitotic responsiveness were regulated by exposure to FSH in vitro.
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PMID:[125I]iodo-epidermal growth factor binding and mitotic responsiveness of porcine granulosa cells are modulated by differentiation and follicle-stimulating hormone. 312 Dec 83

Inhibin levels in the serum-free media of primary Sertoli cell-enriched (SCE) cultures were studied as a function of time and hormonal treatment. SCE cultures were established from 20-day-old rats and maintained in SF media supplemented with insulin, transferrin, epidermal growth factor (EGF), and bacitracin. Radioimmunoassayable inhibin was measured using an antibody directed against a synthetic porcine inhibin-alpha (pI alpha) and measured using this same synthetic peptide as well as a highly purified ovine inhibin standard. Results of these determinations are expressed in terms of a synthetic peptide as femtomoles of pI alpha-(1-26)-G-Y-per ml/10(6) cells. Inhibin levels (+/- SEM) that accumulated at this rate in media from control cultures were 184.9 +/- 6.1 and 167.4 +/- 5.2 on days 0-4 and 4-8, respectively. When FSH (oFSH 17; 1-1000 ng/ml) was added, a dose-dependent increase in inhibin levels was significant at all time points beyond the initial 24 h. The simultaneous addition of 2 x 10(-7) M testosterone (T) with low doses of FSH addition of 2 x 10(-7) m testosterone (T) with low doses of FSH suppressed the inhibin response to FSH, but when T was combined with 300 ng/ml FSH, there was no effect of T on inhibin levels compared to FSH alone, regardless of time in culture. In spite of the modest effect of T, androstenedione (A; 2 x 10(-13) to x 10(-5) M) produced a dose-dependent suppression of inhibin levels. This inhibition was also observed at all doses of FSH. The action of A was not due to its conversion to estrogens, as 17 beta-estradiol had no effect on inhibin production by SCE cultures in either the presence or absence of FSH. The effect of EGF, a component of the basal serum-free medium, was next examined; it produced a 1.5-fold higher level of inhibin (188.7 +/- 9.5) compared to cultures without EGF (135.6 +/- 5.0). When SCE cultures were plated with FSH plus EGF, the stimulation of inhibin levels was additive. We conclude that in Sertoli cell cultures established from immature rats (1) the accumulation of inhibin in medium declines from 90 fmol/10(6) cells.day (initial 24 h) to 40-50 fmol/10(6) cells.day (over the first 48 h) and continues to accumulate in the medium for 8 days of culture; (2) FSH regulates the production of inhibin by Sertoli cells; the best dose response is observed over a 3-day period.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Inhibin production by primary Sertoli cell-enriched cultures: regulation by follicle-stimulating hormone, androgens, and epidermal growth factor. 312 3

Plasma levels of LH, FSH, prolactin (PRL), and testosterone (T) were assessed in six normal men following administration of a pharmacologic dose of gonadotropin releasing hormone (GnRH) (500 micrograms iv over a one-min period) with concomitant oral administration of either ethanol (0.695 g/kg of body weight over a 15-min period) or ethanol placebo. Acute ethanol administration had no effect on the response of either LH or FSH to GnRH. PRL levels increased following GnRH and administration of both ethanol and ethanol placebo. Ethanol administration enhanced the T response to GnRH (p less than 0.001 vs placebo). During the placebo condition, T levels did not rise significantly until 100 min after GnRH administration, at which time the mean increment over baseline was 101 +/- 20 ng/dl (+/- SEM). In contrast, following ethanol intake, T levels were significantly elevated within 30 min after GnRH administration, at which time the mean increment over baseline was 187 +/- 42 ng/dl. The mean T increments were 304 +/- 62 and 472 +/- 77 ng/dl, respectively, 60 and 105 min following GnRH and ethanol administration. The increase in T levels following acute ethanol intake and concomitant gonadotropin stimulation is in contrast to the well-documented effect of chronic ethanol intake on suppression of testosterone synthesis by testicular Leydig cells.
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PMID:Acute ethanol administration enhances plasma testosterone levels following gonadotropin stimulation in men. 312 15

Twenty patients entered a randomized, crossover study of purified follicle-stimulating hormone (pure-FSH) or human menopausal gonadotropin (hMG) superovulation, 2 ampules per day after pituitary desensitization with the luteinizing hormone-releasing hormone (LH-RH) analogue Buserelin (D-Ser tBu6 LH-RH 1-9 ethylamide) nasal spray. There were no cycles cancelled. Six patients conceived (five on pure-FSH, one on hMG). There were 24.2 +/- 2.5 (mean +/- standard error of the mean [SEM]) ampules of pure-FSH and 24.3 +/- 3.6 ampules of hMG stimulation required. There were similar numbers of preoperation follicles: 6.9 +/- 1.0 on hMG and 6.6 +/- 1.1 on pure-FSH, of oocytes collected; 8.5 +/- 1.4 on hMG and 5.8 +/- 1.4 on pure-FSH, and of pre-embryos achieved; 5.1 +/- 0.9 on hMG and 3.4 +/- 1.0 on pure-FSH; on either treatment. The fertilization rate on hMG was 60% and on pure-FSH was 55%. Pre-embryo transfer rates were 3.2 +/- 0.3 in the hMG group and 2.7 +/- 0.4 in the pure-FSH group. There were no differences in serum FSH, LH, estradiol, or progesterone levels between the hMG and pure-FSH groups. Mean +/- SEM luteal phase length was 10.6 +/- 0.4 days in the nonpregnant cycles.
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PMID:A randomized comparative study of purified follicle stimulating hormone and human menopausal gonadotropin after pituitary desensitization with Buserelin for superovulation and in vitro fertilization. 313 51

A prospective study was designed to assess the predictive value of gonadotropin measurements obtained during the early follicular phase upon the hormonal characteristics of the subsequent cycle. The data obtained in 12 normal cycles were used to compute the mean and confidence interval (mean +/- 2 SEM) of the FSH:LH ratio, FSH and LH plasma levels. The limits of the confidence intervals for these different parameters were used to classify the patients. Data of 204 patients were analysed. Low FSH:LH ratios (less than 1.34) are associated with an increase in follicular phase length (+2.4 days), a lower ovulatory rate, but neither luteal phase length nor progesterone levels differ between these two groups. When patients are classified according to FSH levels, our results show that low FSH levels (less than 2.94 mIU/ml) are associated with longer follicular (+2.6 days) and shorter (-1.1 days) luteal phase lengths, but ovulatory rate and progesterone levels in the luteal phase of the ovulatory cycles are similar to those obtained in patients of the normal or high FSH group. High LH levels (greater than 3.15 mIU/ml) are associated with a decreased ovulation rate but follicular and luteal phase characteristics are similar to those obtained in patients in the normal or low LH group. In conclusion, low FSH: LH ratios and low FSH plasma levels measured in the early follicular phase of the cycle are associated with longer follicular phase lengths; but basal gonadotropin measurements have limited predictive value on luteal phase characteristics.
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PMID:Predictive value of the FSH:LH ratio on follicular and luteal phase characteristics of the human menstrual cycle. 314 24

A central, reversible decrease in male sexual function appears related to some aspect of obstructive sleep apnoea (OSA). Lower serum testosterone (T) levels were documented in 15 men with OSA versus nine snorers (no OSA), (9.18 +/- 0.92 vs 11.55 +/- 0.90 nmol/l, mean +/- SEM), P less than 0.05 in a consecutive case series of 24 men referred for diagnostic overnight sleep studies. Gonadotrophins did not differ between the two groups. Although the men with OSA did not differ in body mass index (BMI) or weight from the snorers, they were older (51 +/- 3.9 vs 44 +/- 3.1 years), P less than 0.02. Serum T did not correlate with age, but was correlated with minimum nocturnal arterial oxygen saturation (Min SaO2) (r = 0.589), P less than 0.02. A prospective controlled trial of uvulopalatopharyngoplasty therapy (UPP) for OSA in 12 subsequent subjects showed reproductive improvement which was parallel with improved apnoea at 3 months postsurgery. T increased (13.31 +/- 1.07 to 16.59 +/- 0.72 nmol/l), P less than 0.02, without significant changes in BMI, serum PRL, LH or FSH. All seven of the men who reported decreased sexual interest prior to surgery felt their libido and sexual functioning had returned to normal 3 months following UPP. Some aspect of OSA in men appears to produce a reversible hypothalamic-pituitary reproductive dysfunction.
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PMID:Reversible reproductive dysfunction in men with obstructive sleep apnoea. 314 19


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