Center for Research in Reproduction and Contraception

Permanent URI for this collectionhttps://digital.lib.washington.edu/handle/1773/4284

The Center for Research in Reproduction and Contraception at the University of Washington is dedicated to basic and clinical research focused primarily on the male reproductive system. Under the auspices of the Center, fifteen project investigators are working to understand the biology of this complex system and to apply their findings to problems of infertility and contraceptive development. Their research ranges from the biophysics of cell signaling to clinical trials of hormonal contraceptives. Other important goals are to train young scientists in the methods of reproductive biology and medicine and to maintain cooperative research with institutions in developing countries. Together, the scientists and trainees of the CRRC are addressing some of the most challenging scientific problems as well as the most pressing social issues of our time.

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Distribution and regulation of galanin-like peptide (GALP) in the hypothalamus of the mouse
(Endocrine Society, 2001-12) Johnson, Laura L.; Clifton, Donald K.; Li, Dorothy; Steiner, Robert A.; Teklemichael, Dawit N.; Krasnow, Stephanie M.; Jureus, Anders; Cunningham, Matthew J.
Galanin-like peptide (GALP) is a newly discovered molecule whose expression in the brain is confined to the arcuate nucleus and median eminence. In the rat, cellular levels of GALP mRNA are reduced by fasting and reversed by peripheral administration of leptin. The purpose of this investigation was 1) to clone and map the distribution of GALP mRNA in the brain of the mouse; 2) to compare the pattern and magnitude of GALP mRNA expression in the leptin-deficient obese (ob/ob) mouse with that of wild-type controls; and 3) to examine the effects of leptin delivered into the brain on the expression of GALP mRNA in the ob/ob mouse. We report the sequence of a mouse GALP cDNA and show that GALP mRNA is expressed in the arcuate nucleus, median eminence, infundibular stalk, and the neurohypophysis of this species. The expression of GALP mRNA in the brain was markedly reduced in the ob/ob mice, compared with wild-type animals. Intracerebroventricular infusion of leptin to ob/ob mice increased both the number of GALP mRNA-expressing neurons and their content of GALP mRNA, compared with vehicle-treated controls. These observations demonstrate that GALP mRNA is induced by leptin through a direct action on the brain.
Male hormonal contraception: suppression of spermatogenesis by injectable testosterone undecanoate alone or with levonorgestrel implants in chinese men
(American Society of Andrology, 2004-09) Bremner, William J.; Yang, Pei-Juan; Amory, John K.; Gao, Er-Sheng; Yang, Jie; Zheng, E-Xiang; Gui, You-Lun; He, Chang-Hai
Monthly injections of testosterone undecanoate (TU) act as a male contraceptive by reversibly suppressing spermatogenesis to azoospermia or severe oligoazoospermia in 95% of Chinese men. In 5% of Chinese men, however, monthly TU administered alone fails to suppress spermatogenesis into contraceptive ranges, or sperm "rebound," leading to occurrences of pregnancy during treatment. Since combinations of progestins and androgens are associated with greater degrees of sperm suppression in white men, we hypothesized that the combination of TU and the progestin levonorgestrel (LNG) would result in improved spermatogenic suppression in Chinese men. Sixty-two healthy Chinese men were randomly assigned to one of the following 3 regimens: group I (n = 21) received 4 LNG rods (75 mg each), which were followed 4 weeks later by 500 mg of TU by intra-muscular (IM) injection every 8 weeks for 24 weeks; group II (n = 20) received 4 LNG implants, which were followed 4 weeks later by 1000 mg of TU by IM injection every 8 weeks for 24 weeks; and group III (n = 21) received TU 1000 mg by IM injection every 8 weeks for 24 weeks. Sperm counts, serum testosterone (T), luteinizing hormone, follicle-stimulating hormone, and LNG were measured every 2 weeks before, during, and after treatment. During treatment, group II demonstrated a trend toward a greater attainment of azoospermia than groups I and III (90% vs 62% [group I] vs 67% [group III]; P =.09). Attainments of either azoospermia or oligozoospermia (sperm density, <3 x 10(6)/mL) were 95%, 100%, and 86% for groups I, II, and III, respectively (P >.05 for comparisons between groups). Spermatogenesis in all subjects returned to the normal range after the implants were removed. No serious adverse events and no significant changes in serum chemistry occurred during the study. These results demonstrate that the combination of IM injections of high-dose TU every 2 months and LNG implants is associated with marked suppression of spermatogenesis in Chinese men. The combination of high-dose TU every 2 months and LNG implants is a promising candidate for future large-scale efficacy studies of hormonal male contraception in Chinese men.
Serum inhibin concentrations before and during gonadotropin treatment in men with hypogonadotropic hypogonadism: physiological and clinical implications
(Endocrine Society, 1990-05) Snyder, Peter J.; Bremner, William J.; McLachlan, Robert I.; Finkel, David M.
We measured by RIA the inhibin concentrations in the sera of 20 men with hypogonadotropic hypogonadism before and during treatment with gonadotropins in order to determine the role of gonadotropins in the control of inhibin secretion and the utility of the serum inhibin concentration in assessing the spermatogenic response to gonadotropin treatment in these patients. Before treatment the mean serum inhibin concentration in the 20 hypogonadotropic men as a group (391 +/- 49 U/L) was significantly lower (P less than 0.001) than that in 27 normal men (741 +/- 52 U/L). In the 7 men whose hypogonadism was of postpubertal onset, the mean serum inhibin concentration (559 +/- 69 U/L) was not significantly lower than that in normal men. In the 13 men whose hypogonadism was of prepubertal onset, the serum inhibin level was significantly lower [381 +/- 74 U/L (P less than 0.01) in the 7 without a history of cryptorchidism and 207 +/- 46 U/L (P less than 0.01) in the 6 with a history of cryptorchidism]. All 20 patients were azoospermic or severely oligospermic and had distinctly subnormal serum testosterone concentrations, even those whose serum inhibin values were normal. In the 7 patients with postpubertal hypogonadism, treatment with hCG alone for 6 months increased the serum testosterone concentration and maximum sperm count to normal, even though the previously normal inhibin concentration was not increased further. In the 13 patients with prepubertal hypogonadism, treatment with hCG alone increased the serum inhibin concentration, and combined treatment with hCG and human menopausal gonadotropin (hMG) increased inhibin further, to well within the normal range (742 +/- 143 U/L) in the patients without a history of cryptorchidism and to just within the normal range (487 +/- 96 U/L) in those with such a history. In the 7 patients with prepubertal hypogonadism but no history of cryptorchidism, treatment with hCG and hMG increased the maximum sperm count to normal in 5. In the 6 patients with prepubertal hypogonadism who did have a history of cryptorchidism, hCG and hMG treatment produced a normal sperm count in only 1. Of 12 patients whose serum inhibin level was more than 300 U/L before treatment, 11 developed a normal maximum sperm count in response to treatment, but of 8 patients whose inhibin concentration was less than 300 U/L before treatment, only 2 developed a normal sperm count in response to treatment (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)
Novel male hormonal contraceptive combinations: the hormonal and spermatogenic effects of testosterone and levonorgestrel combined with a 5alpha-reductase inhibitor or gonadotropin-releasing hormone antagonist
(Endocrine Society, 2005-01) McLachlan, Robert I.; Bremner, William J.; Amory, John K.; Matthiesson, Kati L.; Ugoni, Antony; Berger, Richard E.
We postulated that the addition of a combined types I and II, 5alpha-reductase inhibitor (dutasteride) or long-acting GnRH antagonist (acyline) to combination testosterone plus levonorgestrel treatment may be advantageous in the suppression of spermatogenesis for male contraception. This study aimed to examine effects of novel combination contraceptive regimens on serum gonadotropins and androgens and sperm concentration.This study was divided into three phases: screening (2 wk), treatment (8 wk), and recovery (4 wk). Twenty-two men (n = 5-6/group) received 8 wk of treatment with testosterone enanthate (TE, 100 mg im weekly) combined with one of the following: 1) levonorgestrel (LNG) 125 mug orally daily; 2) LNG 125 microg plus dutasteride 0.5 mg orally daily; 3) acyline 300 microg/kg sc every 2 wk (as a comparator for any additional progestin effects); or 4) LNG 125 microg orally daily plus acyline 300 microg/kg sc every 2 wk.Serum gonadotropin levels were similarly suppressed by all treatments, falling to a nadir between 1.2 and 3.4% and 0.5 and 0.8% baseline for FSH and LH, respectively (P < 0.05). Serum dihydrotestosterone levels were significantly (P < 0.05) decreased in the dutasteride group throughout the treatment period to a nadir of 31% baseline (wk 7). No significant differences in sperm concentrations among treatment groups were seen. Severe oligospermia (0.1-3 million/ml) or azoospermia was seen in none of five and four of five in TE + LNG; two of six and four of six in TE + LNG + dutasteride; two of six and four of six in TE + acyline; and one of five and three of five in TE + LNG + acyline groups, respectively. There was one nonresponder in each of the TE + LNG and TE + LNG + acyline groups.We conclude that the addition of a combined types I and II, 5alpha-reductase inhibitor or long-acting GnRH antagonist to a testosterone plus LNG regimen provides no additional suppression of gonadotropins or sperm concentration over an 8-wk treatment period. However, further evaluation of the effects of these regimens on the testis (including testicular steroid levels and germ cell maturation) and the treatment of larger numbers of men (and for longer periods) may provide data to support their place in contraceptive development.
Clusterin in the male reproductive system: localization and possible function
(Elsevier, 1999-05-25) Bailey, Robert; Griswold, Michael D.
Clusterin is a glycoprotein that was initially isolated from the male reproductive system. Subsequently, clusterin has been found to be widely distributed in a variety of tissues in mammals. One characteristic of the expression of clusterin is that it is induced as a result of cellular injury, death, or pathology. Despite the efforts of many laboratories working in diverse biological systems, the function of clusterin remains unknown. Recent studies have revealed a 'heat-shock element' in the promoter of the gene that may account for the inducible nature of the clusterin gene. Overall, the evidence suggests that function of clusterin is to protect surviving cells after damage. This protection may result from a detergent-like action of the protein.
Colchicine and testicular function in man
(Massachusetts Medical Society, 1976-06-17) Bremner, William J.; Paulsen, C. Alvin
The physiological significance of pulsatile LHRH secretion in man: gonadotrophin responses to physiological doses of pulsatile versus continuous LHRH administration
(Blackwell Publishing, 1991-02) Gross, Kenneth M.; Bremner, William J.; Matsumoto, Alvin M.
This study tested whether pulsatile LHRH stimulation of the pituitary is required for normal gonadotrophin secretion in man. Four men with idiopathic hypogonadotrophic hypogonadism (IHH) and presumed endogenous LHRH deficiency were taken off all hormonal replacement for 5-6 weeks, then 5 micrograms LHRH was administered every 2 h for 1 week in order to prime pituitary gonadotrophin responsiveness. A physiological dose of LHRH (10 micrograms every 2 h) was then administered in both pulsatile and continuous regimens, in varying order, to each man. Pulsatile LHRH was capable of stimulating LH (as measured by bioassay) and FSH secretion, while continuous administration of LHRH was not. Serum LH, measured by RIA and bioassay, and FSH and free alpha-subunit levels, measured by RIA, increased significantly (P less than 0.05) over pretreatment levels during pulsatile LHRH administration. In contrast, bioactive LH and immunoactive FSH did not change significantly compared to pretreatment values during continuous infusion of the same total LHRH dose, although immunoactive LH and free alpha-subunit levels did increase significantly (P less than 0.05). The ratio of LH bioactivity to immunoactivity was significantly lower during the continuous compared to pulsatile LHRH regimen (P less than 0.001). Similar serum LHRH levels were achieved during pulsatile and continuous infusions. Serum testosterone and oestradiol levels did not increase significantly from pretreatment levels during either regimen of LHRH administration. It is concluded that a pulsatile LHRH signal pattern is essential for normal pituitary gonadotrophin secretion in men with IHH. Continuous infusion of a physiological dose of LHRH, which produced serum LHRH levels which were indistinguishable from those found during pulsatile administration, failed to stimulate FSH or bioactive LH secretion.
Testosterone replacement in hypogonadal men: effects on obstructive sleep apnoea, respiratory drives, and sleep
(Blackwell Publishing, 1985-06) Lee, Kathryn A.; Bremner, William J.; Schoene, Robert B.; Pierson, David J.; Giblin, Elizabeth C.; Matsumoto, Alvin M.; Sandblom, Robert E.
The obstructive sleep apnoea syndrome occurs predominantly in men. To determine the effect of testosterone on ventilatory function and whether testosterone may play a role in the development of obstructive apnoea, we performed waking ventilatory drive studies and sleep studies in five hypogonadal men. These androgen-deficient subjects were studied both while receiving no treatment and after six weeks of testosterone replacement therapy (testosterone oenanthate 200 mg i.m. every 2 weeks). Hypoxic ventilatory drive decreased significantly, from 158 +/- 39 (mean +/- SEM) off testosterone to 88 +/- 19 on testosterone therapy (P less than 0.05). Hypercapnoeic ventilatory drive did not change significantly on testosterone. Obstructive sleep apnoea developed in one man and markedly worsened in another man in association with testosterone administration. Both of these subjects also exhibited marked decreases in oxygen saturation with the development of cardiac dysrhythmias during sleep and large increases in haematocrit. The remaining three hypogonadal men did not demonstrate significant sleep apnoea either on or off testosterone. The percentage of sleep time spent in REM sleep increased from 14 +/- 3% to 22 +/- 2% when the men were receiving testosterone (P less than 0.01), but the episodes of sleep apnoea tended to occur during non-REM sleep. We conclude that in some hypogonadal men, replacement dosages of testosterone may affect ventilatory drives and induce or worsen obstructive sleep apnoea. The obstructive sleep apnoea syndrome is a potential complication of testosterone therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
Regulation of galanin gene expression in gonadotropin-releasing hormone neurons during the estrous cycle of the rat
(Endocrine Society, 1993-04) Clifton, Donald K.; Vrontakis, Maria; Steiner, Robert A.; Marks, Daniel L.; Smith, M. Susan
Galanin is colocalized with GnRH in neurons of the hypothalamus and basal forebrain of female rats, and this neuropeptide may play a role in the generation of the midcycle surge of gonadotropin secretion. We tested the hypothesis that galanin gene expression in GnRH cells increases during proestrus. To accomplish this, we killed groups of adult female rats at 1200 and 1800 h on the day of proestrus as well as at 1800 h on the day of estrus and used double labeling in situ hybridization and image analysis to estimate and compare the levels of galanin mRNA in cells coexpressing GnRH mRNA. GnRH mRNA was detected with an antisense cRNA probe labeled with the hapten digoxigenin, while the galanin cRNA probe was labeled with 35S and detected by autoradiography. There was no significant difference in the total number of GnRH cells identified in each animal in any of the different groups in any experiment. The relative number of silver grains over these cells, reflecting galanin mRNA content in GnRH neurons (identified by their purple color), was counted with a computerized image analysis system. In an initial experiment, we observed a 2-fold (P < 0.03) higher galanin mRNA signal level in the animals killed at 1800 h than in those killed at 1200 h on the day of proestrus. Animals killed at 1800 h on the day of estrus had galanin mRNA signal levels that were not statistically different from those in the proestrous 1800 h group, indicating that the increase in galanin mRNA at proestrus is maintained for at least 24 h. Galanin mRNA levels in GnRH neurons returned to basal levels equivalent to those in the proestrous 1200 h group by 1000 h on diestrous day 1. In conjunction with the studies of galanin gene expression in GnRH neurons, we compared the relative cellular contents of GnRH mRNA among the same groups. Here, we used single labeling isotopic in situ hybridization for GnRH mRNA and computerized image analysis to count the resulting silver grains. We could detect no difference in GnRH mRNA signal levels (proestrus, 1200 h vs. proestrus, 1800 h vs. estrus, 1800 h). In a final experiment, we investigated the possible role of estrogen in the induction of galanin mRNA expression at proestrus by comparing relative galanin mRNA contents in GnRH neurons among groups of ovariectomized, intact (diestrous day 1), and ovariectomized 17 beta-estradiol-replaced female rats.(ABSTRACT TRUNCATED AT 400 WORDS)
Reproductive aging: accelerated ovarian follicular development associated with a monotropic follicle-stimulating hormone rise in normal older women
(Endocrine Society, 1996-03) Davis, Gretchen S.; Fujimoto, Victor Y.; Soules, Michael R.; Bremner, William J.; Klein, Nancy A.; Battaglia, David E.
Women experience a decline in fertility that precedes the menopause by several years. Previous studies have demonstrated a monotropic rise in FSH associated with reproductive aging: however, the mechanism of this rise and its role in the aging process are poorly understood. The purpose of this study was to characterize ovarian follicular development and ovarian hormone secretion in older reproductive age women. Sixteen women, aged 40-45 yr, with regular ovulatory cycles were studied. The control group consisted of 12 ovulatory women, aged 20-25 yr. Serum obtained by daily blood sampling was analyzed for FSH, LH, estradiol (E), progesterone, and inhibin (Monash polyclonal assay). Follicle growth and ovulation were documented by transvaginal ultrasound. Older women had significantly higher levels of FSH throughout the menstrual cycle. E, progesterone, LH, and inhibin levels did not differ between the two age groups when compared relative to the day of the LH surge. Ultrasound revealed normal growth, size, and collapse of a dominant follicle in all subjects. Older women had significantly shorter follicular phase length associated with an early acute rise in follicular phase E, reflecting accelerated development of a dominant follicle. We conclude that older reproductive age women have accelerated development of a dominant follicle in the presence of the monotropic FSH rise. This is manifested as a shortened follicular phase and elevated follicular phase E. The fact that ovarian steroid and inhibin secretion were similar to those in the younger women suggests that elevated FSH in women of advanced reproductive age may represent a primary neuroendocrine change associated with reproductive aging.
Differential control of luteinizing hormone and follicle-stimulating hormone secretion by luteinizing hormone-releasing hormone pulse frequency in man
(Endocrine Society, 1987-04) Bremner, William J.; Gross, Kenneth M.; Matsumoto, Alvin M.
To test the hypothesis that the frequency of pulsatile LHRH stimulation can differentially control LH and FSH secretion in man, we administered low doses of LHRH in pulsatile fashion in several different regimens to men with idiopathic hypogonadotropic hypogonadism (IHH) and presumed endogenous LHRH deficiency. In study 1, four men with IHH received a constant amount of LHRH per day in three different frequencies. After an initial 7-day period of LHRH (5.0 micrograms every 2 h), the men received 2.5 micrograms every 1 h and 7.5 micrograms every 3 h, each for 4 days, in varying order. Frequent blood samples were obtained before LHRH administration and at the end of each regimen. Before LHRH administration, mean serum FSH and LH levels were low [28 +/- 3 (+/- SEM) and 6 +/- 2 ng/mL, respectively], and they increased into the normal adult male range during LHRH treatment. As the frequency of LHRH administration decreased from every 1 to 2 to 3 h, serum FSH levels progressively increased from 99 +/- 33 to 133 +/- 34 to 181 +/- 58 ng/mL (P less than 0.05). Serum LH levels (34 +/- 6, 33 +/- 6, and 34 +/- 5 ng/mL) were significantly higher than those before LHRH administration and did not differ significantly among the three regimens. Total serum testosterone (T), estradiol, and free T levels were increased by LHRH, but were not significantly different during the three regions of LHRH administration. In study 2, three men with IHH received the same amount of LHRH per dose, given in two different pulse frequencies; 2.5 micrograms LHRH were administered in frequencies of every 0.5 h and every 1.5 h, each for 4 days, in varying order. During the 0.5 h frequency, the mean serum FSH level was 42 +/- 13 ng/mL, and it rose to 80 +/- 19 ng/mL during the 1.5 h frequency (P less than 0.05). Corresponding mean serum LH levels were 25 +/- 5 and 27 +/- 4 ng/mL. Serum T and estradiol levels were not significantly different during the two LHRH regimens. We conclude that the frequency of LHRH stimulation can differentially control FSH and LH secretion by the human pituitary gland, and the pattern of hormonal stimulation may be a determinant of target organ response.
Age trends in the level of serum testosterone and other hormones in middle-aged men: longitudinal results from the Massachusetts male aging study
(Endocrine Society, 2002-02) Johannes, Catherine B.; Bremner, William J.; Derby, Carol A.; McKinlay, John B.; Coviello, Andrea D.; Araujo, Andre B.; Feldman, Henry A.; Longcope, Christopher
We used longitudinal data from the Massachusetts Male Aging Study, a large population-based random-sample cohort of men aged 40-70 yr at baseline, to establish normative age trends for serum level of T and related hormones in middle-aged men and to test whether general health status affected the age trends. Of 1,709 men enrolled in 1987-1989, 1,156 were followed up 7-10 yr afterward. By repeated-measures statistical analysis, we estimated simultaneously the cross-sectional age trend of each hormone between subjects within the baseline data, the cross-sectional trend between subjects within the follow-up data, and the longitudinal trend within subjects between baseline and follow-up. Total T declined cross-sectionally at 0.8%/yr of age within the follow-up data, whereas both free and albumin-bound T declined at about 2%/yr, all significantly more steeply than within the baseline data. Sex hormone-binding globulin increased cross-sectionally at 1.6%/yr in the follow-up data, similarly to baseline. The longitudinal decline within subjects between baseline and follow-up was considerably steeper than the cross-sectional trend within measurement times for total T (1.6%/yr) and bioavailable T (2-3%/yr). Dehydroepiandrosterone, dehydroepiandrosterone sulfate, cortisol, and estrone showed significant longitudinal declines, whereas dihydrotestosterone, pituitary gonadotropins, and PRL rose longitudinally. Apparent good health, defined as absence of chronic illness, prescription medication, obesity, or excessive drinking, added 10-15% to the level of several androgens and attenuated the cross-sectional trends in T and LH but did not otherwise affect longitudinal or cross-sectional trends. The paradoxical finding that longitudinal age trends were steeper than cross-sectional trends suggests that incident poor health may accelerate the age-related decline in androgen levels.
Spnr, a murine RNA-binding protein that is localized to cytoplasmic microtubules
(Rockefeller University Press, 1995-05) Braun, Robert E.; Edelhoff, Susanne; Schumacher, Jill M.; Lee, Keesook
Previous studies in transgenic mice have established the importance of the 3' untranslated region (UTR) of the spermatid-specific protamine-1 (Prm-1) mRNA in its translational control during male germ cell development. To clone genes that mediate the translational repression or activation of the Prm-1 mRNA, we screened cDNA expression libraries made with RNA from pachytene spermatocytes and round spermatids, with an RNA probe corresponding to the 3' UTR of Prm-1. We obtained six independent clones that encode Spnr, a spermatid perinuclear RNA-binding protein. Spnr is a 71-kD protein that contains two previously described RNA binding domains. The Spnr mRNA is expressed at high levels in the testis, ovary, and brain, and is present in multiple forms in those tissues. Immunolocalization of the Spnr protein within the testis shows that it is expressed exclusively in postmeiotic germ cells and that it is localized to the manchette, a spermatid-specific microtubular array. Although the Spnr protein is expressed too late to be directly involved in the translational repression of Prm-1 specifically, we suggest that the Spnr protein may be involved in other aspects of spermatid RNA metabolism, such as RNA transport or translational activation.
Human chorionic gonadotropin and testicular function: stimulation of testosterone, testosterone precursors, and sperm production despite high estradiol levels
(Endocrine Society, 1983-04) Rebar, Robert W.; Hopper, Bill R.; Bremner, William J.; Matsumoto, Alvin M.; Paulsen, C. Alvin
Age-related analysis of inhibin A, inhibin B, and activin a relative to the intercycle monotropic follicle-stimulating hormone rise in normal ovulatory women
(Endocrine Society, 2004-06) Woodruff, Teresa K.; Soules, Michael R.; Hansen, Karl R.; Bremner, William J.; Sluss, Patrick M.; Klein, Nancy A.; Houmard, Brenda S.
Previous studies have reported that the monotropic rise in FSH in older women is associated with decreased inhibin B and/or A levels and increased levels of activin A. Whereas most investigators have found decreased follicular-phase inhibin B, the roles of inhibin A and activin A as modulators of the FSH rise are unclear. The objectives of this study were to determine whether deficiencies in circulating levels of inhibin A, inhibin B, and/or activin A exist during the intercycle interval in ovulatory older (age, 40-45 yr; n = 16), compared with younger women (age, 20-25 yr; n = 13). Blood samples were obtained daily throughout one menstrual cycle and the follicular phase of the subsequent cycle and were analyzed for LH, FSH, estradiol, inhibin A and B, and activin A. Despite significant FSH elevation, no deficiencies in inhibin A, activin A, or estradiol were detected in older subjects. In fact, inhibin A was significantly higher in older participants during the intercycle phase (P = 0.01), whereas inhibin B was significantly lower. Thus, the monotropic rise in FSH does not appear to result from changes in inhibin A or activin A, supporting the concept that inhibin B plays a critical role in mediating the FSH rise in older women.
Elevated serum follicle-stimulating hormone levels in men with normal seminal fluid analyses
(Elsevier, 1983-03) Bremner, William J.; Paulsen, C. Alvin; Karpas, Anthony E.; Matsumoto, Alvin M.
Three men who volunteered as normal subjects were found to have abnormally high levels of serum follicle-stimulating hormone (FSH) despite having normal seminal fluid analyses and fertility. Two of the men had a history of previous orchitis, and one had an atrophic testis. Serum luteinizing hormone and testosterone levels were normal. These cases appear to represent compensated primary testicular disease, with normal sperm counts and fertility maintained at the expense of chronically elevated FSH levels. These results imply that in certain situations, the measurement of serum FSH levels may be a more sensitive index of testicular disease than the performance of seminal fluid analyses.
Leptin is a metabolic signal to the reproductive system
(Endocrine Society, 1996-07) Ren, Hongping; Clifton, Donald K.; Weigle, David S.; Steiner, Robert A.; Kuijper, Joseph L.; Kabigting, Emilia B.; Barash, Ilona A.; Cheung, Clement C.
Leptin, a newly-discovered hormonal product of the obese (ob) gene, is expressed by adipocytes and thought to play a role in the regulation of food intake and metabolism. We tested the hypothesis that leptin signals metabolic information to the reproductive system by examining its effects on the reproductive system of ob/ob mice, which have a congenital deficiency in leptin and are infertile. We treated pair-fed males and females with leptin (50 microg twice daily, ip) or vehicle (n=10/group) for 14 days, after which the animals were bled and killed. Leptin-treated females had significantly elevated serum levels of LH, increased ovarian and uterine weights, and stimulated aspects of ovarian and uterine histology compared to controls. Leptin-treated males had significantly elevated serum levels of FSH, increased testicular and seminal vesicle weights, greater seminal vesicle epithelial cell height, and elevated sperm counts compared to controls. These results demonstrate that leptin stimulates the reproductive endocrine system in both sexes of ob/ob mice and suggest that leptin may serve as a permissive signal to the reproductive system of normal animals.
An automated technique for the radiographic determination of bone age
(Blackwell Publishing, 1982) Steiner, Robert A.; Clifton, Donald K.; Bremner, William J.
We have developed an automated procedure for determining bone-age in the monkey, Macaca fascicularis. The status of epiphysial junctions and sesamoids were determined from radiographs. Epiphyses were scored as either open or closed, and sesamoids were scored as either present or absent. Bone-age was calculated by a computer program that stored and used a data base of probabilities for epiphysial closure and sesamoid appearance. The simplicity of scoring, combined with the speed and accuracy of the calculations, make this technique potentially adaptable for use in a variety of primate species.
Molecular genetic analysis of mammalian spermatid differentiation
(Endocrine Society, 1995) Schumacher, Jill M.; Fajardo, Mark A.; Braun, Robert E.; Lee, Keesook
Immunohistochemical localization of androgen receptors in the rat testis: evidence for stage-dependent expression and regulation by androgens
(Endocrine Society, 1994-09) Saunders, Philippa T. K.; Sharpe, Richard M.; Bremner, William J.; Millar, Michael R.
Androgens are essential for the maintenance of normal spermatogenesis in the rat. We assessed the sites, developmental pattern, and hormonal control of androgen receptors (AR) in the rat testis. Adult male rats were studied after 1) no treatment; 2) ethane dimethane sulfonate (EDS), which eradicates Leydig cells and endogenous testosterone (T); 3) EDS plus T replacement beginning at the time of EDS administration; or 4) methoxyacetic acid, which leads to the loss of specific germ cell types. Testes were also obtained from normal immature rats (aged 5, 14, 16, 21, 28, 31, 35, 38, and 45 days). After microwave antigen retrieval, immunohistochemistry was performed using a rabbit polyclonal antibody (Novocastra) raised against a peptide unique to the N-terminal region of the AR and detection with biotinylated swine antirabbit immunoglobulin G, avidin-biotin complex/alkaline phosphatase, and nitroblue tetrazolium salt (NBT)/5 bromo-4-chloro-3-indolylphosphate (BCIP) substrate. In adults, nuclear immunostaining of Sertoli cells (SC) increased progressively in intensity from stages II through VII of the spermatogenic cycle, and then declined precipitously during stage VIII to become barely detectable in stages IX-XIII. Prominent AR immunostaining was also evident in peritubular myoid cells, arterioles, and interstitial cells; staining in these cells did not vary with the stage of the cycle of the adjacent tubules. EDS caused a severe loss of AR immunostaining in all cell types. Replacement of T in EDS-treated animals resulted in a pattern of AR immunostaining comparable to that in controls, although staining intensity was reduced. Methoxyacetic acid administration did not affect the pattern of AR staining. In immature rats, peritubular myoid cell immunostaining was prominent from day 5; SC staining was detectable on day 5, increased in intensity with age, and became stage dependent between days 21-35. The following conclusions were reached. 1) Immunohistochemically detectable AR expression in SC occurs predominantly in stages II-VII of the spermatogenic cycle, with highest levels at stage VII. 2) AR immunostaining is also prominent in peritubular myoid cells, arterioles, and Leydig cells (but not in germ cells), but is unrelated to the stage of adjacent tubules. 3) Endogenous T and/or its metabolites control the expression of AR in the testis. 4) AR immunostaining is detectable by day 5 of age and becomes stage specific in SC between days 21-35.

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