Plasma testosterone and dihydrotestosterone in normal and abnormal pregnancy

Effects of in vivo dihydrotestosterone treatment on changes in nocturnal surge of prolactin, luteal ultrastructure and P-450scc mRNA and protein content in pregnant rats

We have demonstrated previously that the administration of dihydrotestosterone (DHT) decreases plasma progesterone levels within 24 h and thus, results in abortion during the first half of pregnancy (Am. J. Physiol. 241 (1981) E444-E448). The purpose of this study was to determine (a) if the administration of DHT suppresses plasma prolactin levels or its nocturnal surge within 24 h after the treatment, (b) how soon after the commencement of treatment do the concentrations of DHT increase and progesterone levels decrease in the circulation, (c) the ultrastructural changes that occur in corpora lutea, and (d) the changes in luteal P-450 side-chain cleavage (P-450scc) enzyme and mRNA content upon DHT treatment. Within 24 h after the commencement of DHT treatment, the nocturnal surge of prolactin, detected in both groups on day 10 at 03.30 h, was inhibited in DHT-treated rats as compared to controls. The non-surge levels of prolactin at 05.00 and 06.00 h were not different between groups. The intraovarian DHT pellet increased plasma levels of the steroid 3-fold within 2 h (blood samples were taken at 2-hourly intervals) when compared to controls. By 24 h DHT levels were decreased but were still higher than controls. Plasma progesterone levels began to fall 6 h after the commencement of treatment. Luteal tissue from animals treated with DHT appeared steroidogenic, and contained more lipid droplets than controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased maternal serum 3 alpha, 17 beta-androstanediol glucuronide concentrations during pregnancy

Maternal serum concentrations of 3 alpha, 17 beta-androstanediol glucuronide (3 alpha-diol-G), a substance that reflects peripheral androgen action and tissue 5 alpha-reductase activity, were measured in 33 normal men, 51 nonpregnant women, and 51 women with uncomplicated pregnancies. The 3 alpha-diol-G concentrations in men (median, 201 ng/ml) were significantly higher than in nonpregnant women (median, 42 ng/ml) or pregnant women (median, 124 ng/ml). The concentrations in pregnant women were significantly greater than those in nonpregnant women, and there were no significant differences between trimesters in maternal 3 alpha-diol-G concentrations. There were no fetal sex differences found in maternal serum or in third-trimester amniotic fluid. These results indicate that pregnancy is associated with increased androgen production by maternal tissues and that fetal 3 alpha-diol-G production is low.

Alterations in the androgen metabolism of the female guinea-pig during pregnancy

The peripheral conversion of testosterone (T) into androstenedione (delta 4) and dihydrotestosterone (DHT) were studied in pregnant (days 32, 48 and 67 post coitum) and non-pregnant anesthetized guinea-pigs by constant intravenous infusion of tritium labeled T. Endogenous levels were measured by radioimmunoassay, and the three labeled androgens (T*, DHT* and delta 4*) counted after celite chromatography. The endogenous T, DHT and delta 4 plasma concentrations were respectively 5, 7 and 20 times higher in pregnant females than they were in cyclic ones. In the non-pregnant guinea-pig, no part of the delta 4 or DHT pools was derived from the peripheral conversion of testosterone. On days 32, 48 and 67 of gestation the fractions of the delta 4 pool originating from T were 9.1, 13.1 and 15.1%, and the fractions of DHT pool coming from T were 5.1, 22.1 and 21.3% respectively.

An association between serum testosterone level and HLA phenotype

The concentration of testosterone was determined in sera of 122 HLA-typed women. Subsequently the women were classified in the category below or above the mean serum testosterone concentration. When the frequencies of HLA antigens were compared in these two categories of women, it was found that HLA-B5 and HLA-B12 antigens were significantly increased in the category of women with serum testosterone level above the mean concentration (P less than 0.01 and P less than 0.05, respectively). The frequency of HLA-B8 antigen was significantly decreased in the same category of women (P less than 0.05). The comparisons of the mean testosterone values of each HLA antigen and the variance analysis have also shown significant differences between the mean of HLA-B8 antigen and the means of other HLA antigens--HLA-A2, A3, A9, B5, B12 and Bw35. These results gave further conclusive evidence that gene(s) inside HLA region influence either the androgen hormone metabolism itself or cellular sensitivity to hormonal action as it has been presented for congenital adrenal hyperplasia.