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W H Moger

Publications and source records attributed to W H Moger.

64 records · Page 4Linked to original sources
PubMed1975

Effects of testosterone metabolites on serum gonadotropin concentrations in immature male rats.

The ability of testosterone, androsterone, 5alpha-androstane-3alpha,17beta-diol, and 5alpha-androstane-3beta,17beta-diol to prevent the castration-induced rise in serum gonadotropin levels was investigated in immature male rats. Rats castrated at 30 days of age were treated once per day by subcutaneous injection of 12.5-100 mug of the steroid per 100 g body weight per day for 3 days, beginning on the day of castration. The animals were sacrificed 24 h after the last injection. Testosterone propionate, androsterone propionate, and 5alpha-androstane-3alpha,17beta-diol dipropionate were also tested at the approximate molar equivalent of 100 mug of the free alcohol form per 100 g body weight per day. Testosterone propionate and 5alpha-androstane-3alpha,17beta-diol were the only compounds tested that prevented the castration induced rise in luteinizing hormone (LH) concentrations. Testosterone propionate also inhibited the rise in follicle stimulating hormone (FSH) concentrations whereas 5alpha-androstane-3alpha,17beta-diol inhibited the rise in FSH in one but not in another experiment. These were the only compounds tested that affected serum FSH concentrations. The lower doses of testosterone tested significantly increased serum LH, but not FSH concentrations compared to castrate control animals. The highest dose tested partially inhibited the rise in serum LH concentrations. Both androsterone and androsterone propionate maintained ventral prostate weights. Although neither compound prevented the castration induced rise in serum LH, two groups receiving androsterone had serum LH concentrations significantly lower than the castrate control group. 5alpha-Androstane-3beta,17beta-diol and 5alpha-androstane-3alpha,17beta-diol dipropionate failed to maintain ventral prostate weights or prevent the rise in serum gonadotropin levels. These results indicate that 5alpha-androstane-3alpha,17beta-diol is capable of preventing the castration induced rise in serum LH concentrations in the immature male rat and thus may participate in the regulation of LH secretion in these animals.

Androstane-3,17-diol↗
PubMedDate not supplied

Uptake and release of ascorbic acid by rat Leydig cells in vitro.

The mechanism by which ascorbic acid is transported into rat Leydig cells in vitro was investigated. Transport of [14C]ascorbic acid was temperature-dependent and inhibited in the absence of sodium in the incubation medium. The uptake of [14C]ascorbic acid was saturable (apparent Km approximately equal to 33 microM, Vmax approximately equal to 20 pmol/10(6) cells/min) and stereospecific. Uptake was not affected by removing glucose from the incubation medium, indicating that no significant uptake was occurring via the glucose transport system. Transport of [14C]ascorbic acid into Leydig cells was not affected by testosterone concentrations up to 7 microM or by LH at a concentration that causes maximum androgen secretion. Leydig cells preloaded with [14C]ascorbic acid rapidly released radioactivity into the incubation medium, a process that was unaffected by the presence of LH. The results suggest that ascorbic acid uptake by Leydig cells is by an electroneutral, sodium-dependent co-transport mechanism as in some, but not all, other types of cells.

Animals↗
PubMedDate not supplied

Neuroendocrine control of ovarian autografts.

At 24 days of age, either one or both ovaries of female rats were removed and transplanted subcutaneously on their respective side. Relative to sham operated rats, endocrine effects of the ovarian grafts were as follows: 1) Animals with ovarian grafts showed an advancement of puberty, 2) rats with bilateral grafts showed more 5 day estrous cycles and higher FSH levels, 3) hemi-ovariectomy of animals with bilateral grafts produced a greater increase in both LH and FSH 6-8 hr post-surgery in contrast to controls which only showed an increase in serum FSH levels, 4) weights of the bilateral grafts were comparable to intact ovaries, but the unilateral grafts were small and comparable to their original size at the time of transplantation (the intact ovary showing compensatory hypertrophy), 5) both control and bilateral ovarian graft groups showed ovarian compensatory hypertrophy, 6) removal of the small unilateral ovarian graft had no detectable endocrine effect on the remaining intact ovary which had already undergone compensatory hypertrophy, 7) removal of the intact ovary of rats with a unilateral graft produced a remarkable increase in the weight of the remaining small autograft such that these animals had the largest remaining gonad as well as higher uterine weights than controls. Thus, although ovarian autografts appear to function similar to in situ glands, the alterations in puberty, estrous cycles, FSH and LH levels and uterine weights suggest that endocrine control mechanisms are altered in rats with ovarian grafts.

Animals↗