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Ovarian estradiol (E2) production is regulated by complex interaction of different hormones, such as gonadotropins, steroids, and growth factors. Despite the key role of 17 beta-hydroxysteroid dehydrogenase (17HSD) in E2 biosynthesis, little is known about its regulation in the ovary. Recently, we have characterized the structure of rat 17HSD type 1 and demonstrated that its expression is regulated by gonadotropins and diethylstilbestrol (DES) in rat ovary in vivo. In the present study, the hormonal regulation of 17HSD type 1, and the expression of cytochrome P450 aromatase were examined in parallel in cultured granulosa cells obtained from DES-primed immature rats. Under these conditions, the cells show high expression of 17HSD type 1. Both the enzyme activity and 17HSD type 1 messenger RNA expression in these cells decreased over 2 days of culture in serum-free medium. However, recombinant FSH (recFSH) partially prevented the decreases in enzyme activity and messenger RNA expression in a dose-dependent manner. This effect appears to be mediated by a cAMP-dependent pathway. In contrast to recFSH, neither estrogens (DES or E2) nor androgens (testosterone or dihydrotestosterone) alone affected expression of the enzyme in the cultured cells. However, both estrogens and androgens clearly enhanced the effect of recFSH on 17HSD type 1 expression and 17HSD activity in a dose-dependent manner. Among the growth factors, epidermal growth factor (EGF) has previously been shown to decrease the expression of cytochrome P450 aromatase and E2 biosynthesis in granulosa cells. In the present study, we found that treatment with EGF caused a marked decrease in the effect of recFSH on 17HSD type 1 expression and 17HSD activity. The fact that 17HSD type 1 expression and 17HSD activity always behaved in parallel suggests that 17HSD type 1 is the major 17HSD enzyme involved in estradiol biosynthesis in rat granulosa cells. In conclusion, these data indicate that expression of 17HSD type 1 in rat granulosa cells is under multihormonal regulation. The enzyme is regulated by FSH, via cAMP, and the effect of FSH is modulated by estrogens, androgens, and EGF.

The mechanisms by which ethanol (EtOH, 1.5 g/kg) inhibits testicular testosterone synthesis were studied in nonstimulated and human chorionic gonadotropin (hCG, 50 IU/kg)-treated male rats. To dissociate the effects caused by ethanol metabolism, the alcohol dehydrogenase inhibitor 4-methylpyrazole (4MP, 10 mg/kg) was given to half of the rats 30 min before EtOH. The 4MP had little or no effect in the nonstimulated rats on the EtOH-induced decreases in the concentrations of serum testosterone and of the intratesticular steroids of the testosterone biosynthetic pathway measured, but reduced the EtOH-induced elevation in the intratesticular pregnenolone-to-progesterone ratio. In contrast, 4MP pretreatment markedly reversed the EtOH-induced decrease in serum and intratesticular testosterone and increase in intratesticular pregnenolone concentrations in the hCG-stimulated rats. Simultaneously, the EtOH-induced elevations in the intratesticular pregnenolone/progesterone and androstenedione/testosterone ratios were abolished. In the EtOH-treated rats whose EtOH metabolism was blocked by 4MP pretreatment, the intratesticular testosterone concentrations were negatively correlated with the elevated serum corticosterone levels. It is concluded that: (1) EtOH metabolism is involved in the inhibition of testicular steroidogenesis in vivo. This effect is pronounced during gonadotropin-stimulated conditions. Thus, previously reported "discrepancies" between the in vivo and in vitro results are clarified; (2) corticosterone seems also to be involved in the EtOH-induced inhibition of steroidogenesis. This effect is also pronounced during gonadotropin-stimulated conditions; and (3) without external gonadotropin stimulation other inhibitory mechanisms, such as decreased stimulation by luteinizing hormone, are prevalent.

The concentrations of prostate-specific acid phosphatase (PAP), testosterone, 5 alpha-dihydrotestosterone (5 alpha-DHT), 5 alpha-androstane-3 alpha, 17 beta-diol, androstenedione, 5 alpha-androstanedione, and androsterone were measured by specific radioimmunoassays in whole pieces and in separated epithelium from human benign prostatic hypertrophic (BPH) tissues. Significant correlations were noted between the concentrations of PAP and 5 alpha-DHT, and PAP and 5 alpha-androstane-3 alpha, 17 beta-diol in the epithelium, and between PAP and androstenedione, and PAP and testosterone PAP is androgen dependent, particularly as regards 5 alpha-DHT, whereas 5 alpha-androstane-3 alpha, 17 beta-diol may operate after conversion to 5 alpha-DHT. There is no obvious explanation for the correlations noted in whole tissue, but is suggested that circulating androgens, representing the androgen source for the prostate, primarily determine the production of PAP. The majority of the PAP in BPH tissues is located extracellularly.

The search for major abnormalities as causes for breast cancer have not been successful, whether they have been directed to patients with this disease, different groups, or populations at risk. Anovulation or progesterone deficiency are not characteristic for those at risk for breast cancer or those patients with early breast cancer. In contrast, early-onset long-lasting ovulatory cycle function seems to be prevalent in different risk categories. Women with early menarche are additionally characterized by having higher serum estradiol and lower sex hormone-binding globulin concentrations than women with later menarche, at least during the early years of their fertile life. Estradiol is a central agent in the process of breast cancer appearance, and progesterone does not seem to have an opposing action. A decrease in the number of ovulatory cycles may exert a protective effect against breast cancer. If the decrease is affected by endocrine mechanisms maintaining breast ethelial stimulation comparable to that during the normal menstrual cycle, the protective effect would be nullified.

Prostate tissues removed from patients with benign prostatic hypertrophy were separated into epithelial and stromal components and nuclei purified from these. The concentrations of testosterone, 5 alpha-dihydrotestosterone, 5 alpha-androstane-3 alpha,17 beta-diol, 4-androstene-3,17-dione, 5 alpha-androstanedione and androsterone in pooled preparations of the purified nuclei were determined by radioimmunoassays after the purification of solvent steroid extracts by Lipidex-5000 column chromatography. The most abundant androgen measured was 5 alpha-dihydrotestosterone and it was significantly (P less than 0.05) more concentrated in the stromal nuclei than in the epithelial nuclei. The mean concentration of androsterone was also significantly (P less than 0.05) greater in the stromal nuclei whereas that of testosterone was equal in the two nuclear types. The concentrations of 5 alpha-androstane-3 alpha,17 beta-diol, 4-androstene-3,17-dione and 5 alpha-androstanedione were below the sensitivity limits of the assays in the majority of cases, but the results indicated that when detectable the first two were more concentrated in the stromal than the epithelial nuclei. The results emphasize the importance of the prostatic stroma in androgen metabolism, and the relative concentrations of 5 alpha-dihydrotestosterone and testosterone indicated identical 5 alpha-reductase activities in the nuclei in comparison with respective whole cell epithelial and stromal preparations. 5 alpha-Dihydrotestosterone concentrations were clearly higher than the nuclear androgen receptor levels previously reported from this laboratory.

In order to assess the extent of inhibition of testicular steroidogenesis during long-term treatment of prostatic cancer with GnRH agonist, we measured the intratesticular levels of 5 steroid sulfate conjugates in human testis tissue removed from patients after 6 months of intranasal treatment with buserelin. The most pronounced decreases were found in testosterone and pregnenolone sulfates, to 1.6 and 7.1%, respectively, of concentrations measured in testis tissue from primarily orchiectomized prostatic cancer patients. In contrast, clearly smaller decreases were found in three other steroid sulfates measured, those of dehydroepiandrosterone (to 26%), 17-hydroxyprogesterone (to 27%) and 5-androstene-3 beta, 17 beta-diol (to 62%). These results are in keeping with our previous analyses of unconjugated steroids in similar tissue samples, and indicate that testicular steroidogenesis per se is not totally blocked by long-term intranasal treatment with GnRH agonist. Testicular steroid sulfate conjugation may be specifically suppressed since the total concentration of these conjugates decreased more than free steroid levels in our earlier measurements.

The responses of peripheral serum steroids to a single injection of hCG (80 IU/kg b wt) were compared in adult male rats and humans. Before hCG, the quantitatively dominating steroids were dehydroepiandrosterone, testosterone and 17-hydroxypregnenolone in the men, and testosterone and progesterone in the rats. One hour after hCG the concentrations of testosterone and all its precursors measured except for pregnenolone were significantly elevated in the rat serum, whereas a clear rapid response was not observed in the men. Transient blockade of C21 steroid side-chain cleavage was seen in both species at about 24-36 h after hCG, which occurred at the same time as the maximum concentration of estradiol in the men. No changes in rat serum estradiol concentrations were observed. Both species showed a secondary stimulation of testosterone and androstenedione formation at around 3 days. Our findings are compatible with the concept that the main difference in the gonadotropin-stimulated steroidogenesis in man and rat is the magnitude of the rapid steroidogenic response to hCG, which is very small in man and indicates smaller supply or lesser metabolism of mitochondrial cholesterol in human testis.

The short-term effects of the administration of estradiol on testicular steroid production were assessed by measuring the serum concentrations of testosterone, and a number of its precursors and metabolites, in the spermatic and peripheral veins of five inguinal hernia patients and one untreated prostatic carcinoma patient, as well as in 18 patients with advanced prostatic carcinoma, treated for 1 to 9 days with a single injection of 80 mg of polyestradiol phosphate (Estradurin). With the exception of progesterone, the treatment resulted in a significantly decreased testicular production of all steroids measured in spermatic vein serum; the same finding holds true for concentrations of testosterone, 5 alpha-dihydrotestosterone, and 17 alpha-hydroxyprogesterone in peripheral vein serum before and after treatment. By comparing the steroid concentrations in the spermatic and peripheral veins it is evident that the testicular production of all steroids measured persisted, although at a decreased level, even 7 to 9 days after Estradurin administration; this was most pronounced in the case of testosterone and 17 alpha-hydroxyprogesterone. It is apparent that the effect of estradiol on testicular steroid production is a gradual process which takes several days before it is clearly evident.

60 patients (139 blood specimens) with Turner's syndrome were investigated in order to obtain information concerning the origin of the increments of androgens during puberty. The concentrations of serum FSH, LH, estradiol, testosterone, 5 alpha-dihydrotestosterone, dehydroepiandrosterone, progesterone, 17-hydroxyprogesterone and pregnenolone in patients less than 10 years old were identical to those previously found in normal healthy girls of the same age. Hence, in adrenarche the early increase of androgen secretion is independent of gonadal hormone secretion. The later increases in serum testosterone and androstenedione in our patients were very small, and the age of 15 years, their concentrations were 50 and 60%, respectively, of the corresponding levels in normal girls of the same age. After 13 years of age, the mean serum dehydroepiandrosterone concentration was also slightly, but significantly (20-30%), lower than in normal girls of the same age. It is concluded that the ovaries are responsible for most of the pubertal rises in circulating testosterone and androstenedione, and possibly for a small part of the late pubertal rise in dehydroepiandrosterone.

LH/hCG binding and concentrations of pregnenolone, progesterone, 17-hydroxy-progesterone, androstenedione, testosterone and 5 alpha-dihydrotestosterone were measured in testicular tissue obtained from patients undergoing orchiectomy for prostatic cancer. One group of the orchiectomized patients had received an injection of 80 mg polyestradiol phosphate 1-9 days before the operation, another group were treated with monthly injections of the oestrogen for several months, and the remainder were not treated with oestrogen. In non-oestrogen treated patients (n = 8) the hCG-binding capacity was 28.0 +/- 15.0 (SD) ng/g and the equilibrium association constant of binding was 0.69 +/- 0.38 x 10(10) M-1. The binding capacity was significantly (P less than 0.025) lower (10.3 +/- 8.7 ng/g) in patients (n = 6) receiving the first oestrogen injection 3-9 days prior to the operation. A further decline to the level of 1.77 +/- 1.03 ng/g occurred in patients (n = 3) treated over 3 months with the oestrogen injections. At the same time, no significant changes were observed in peripheral serum LH and FSH levels. In the testicular endogenous steroid levels, statistically significant decreases were seen 9 days after the oestrogen injection in pregnenolone (from 505 +/- 315 ng/g to 138 +/- 86 ng/g) and in testosterone (from 669 +/- 243 ng/g to 254 +/- 49 ng/g) whereas no significant changes could be seen in the levels of the other steroids analysed. This study gives further evidence for the direct inhibitory action of oestrogens on human testicular steroidogenesis and suggests that the loss of testicular luteinizing hormone receptors may be one facet of this inhibitory action.

The influence of high doses of testosterone and anabolic steroids on testicular endocrine function and on circulating steroid binding proteins, sex hormone binding globulin (SHBG) and cortisol binding globulin (CBG), were investigated in power athletes for 26 weeks of steroid self-administration and for the following 16 weeks after drug withdrawal. Serum testosterone and androstenedione concentrations increased (P less than 0.05) but pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone, 5-androstene-3 beta, 17 beta-diol, progesterone and 17-hydroxyprogesterone concentrations strongly decreased (P less than 0.001) during steroid administration. Serum pregnenolone, 17-hydroxypregnenolone and dehydroepiandrosterone sulphate concentrations followed the changes of the corresponding unconjugated steroids but 5-androstene-3 beta, 17 beta-diol and testosterone sulphate concentrations remained unchanged during the follow-up time. During drug administration SHBG concentrations decreased by about 80 to 90% and remained low even for the 16 weeks following steroid withdrawal. Steroid administration had no influence on serum CBG concentrations. In conclusion, self-administration of testosterone and anabolic steroids soon led to impairment of testicular endocrine function which was characterized by low concentrations of testosterone precursors, high ratios of testosterone to its precursor steroids and low SHBG concentrations. Decreased concentrations of SHBG and testicular steroids were still partly evident during the 16 weeks after drug withdrawal. The depressed circulating levels of dehydroepiandrosterone and its sulphate may indicate that the androgenic-anabolic steroids also suppress adrenal androgen production.

Serum concentrations of testosterone, 17-hydroxyprogesterone, estradiol and several other unconjugated and sulphated steroids were analyzed before and after a single dose of hCG in 6 power athletes, who had used high doses of testosterone and anabolic steroids for 3 months. The study was carried out 3 weeks after cessation of drug use, but the study subjects were still characterized by hypogonadotrophic hypogonadism. The mean concentrations of serum LH and FSH were 2.6 +/- 0.3 and 1.1 +/- 0.03 mIU/ml (mean +/- SEM), respectively, and the concentrations of several precursors and metabolites of testosterone were lower than those before drug use. In contrast, circulating concentrations of steroid sulphates were not decreased, with the exception of dehydroepiandrosterone sulphate. After hCG injection serum testosterone and 5 alpha-dihydrotestosterone concentrations increased significantly, whereas no increases in estradiol and 17-hydroxyprogesterone concentrations were observed. These results demonstrate that during transient hypogonadotrophism in adult men, the testicular responsiveness to a single injection of hCG is similar to that in prepubertal boys without any sign of steroidogenic lesion at the 17,20-desmolase step. Therefore, the appearance of the possibly estradiol-mediated inhibition at the level of C21-steroid side-chain splitting in testosterone biosynthesis seems to be dependent on priming by gonadotrophins.

Twenty-one samples of surgically removed benign prostatic hypertrophy (BPH) were brought to the laboratory either in an insulated container (ambient temperature) or on ice. They were cleaned and roughly minced at room temperature. In 18 cases, samples of up to 1 g were kept at various temperatures (4 degrees C, c. 20 degrees C, and 37 degrees C) for up to 77 h; some were taken for storage (-70 degrees C) at the beginning and others at various times within this period. In three cases, portions of tissue were incubated in liquid medium in the absence and presence of testosterone. The concentrations of six androgens (testosterone, 5 alpha-dihydrotestosterone (5 alpha-DHT), 5 alpha-androstane-3 alpha, 17 beta-diol, androstenedione, 5 alpha-androstanedione, and androsterone) were measured by radioimmunoassays. The results indicated that in conditions resembling those after death, the BPH tissue content of 5 alpha-DHT falls to a variable degree, while concentrations of 5 alpha-androstane-3 alpha, 17 beta-diol, 5 alpha-androstanedione, and androsterone increase. After 2 to 3 days, the 5 alpha-DHT concentrations remained greater than those reported previously from this laboratory (and others) in normal prostate tissue removed at autopsy.

Prostate tissues removed from patients with benign prostatic hypertrophy were separated into epithelia and stromal components and the concentrations of testosterone, 5 alpha-dihydrotestosterone, 5 alpha-androstane-3 alpha,17 beta-diol, 4-androstene-3,17-dione, 5 alpha-androstanedione and androsterone in these two fractions were determined by radioimmunoassays after the purification of solvent steroid extracts by Lipidex-5000 column chromatography. On a 'per cell' basis (i.e. relative to DNA), testosterone was equally distributed between the two components, while the other androgens measured were more abundant in the stroma. The observation that 5 alpha-reduced androgens (especially 5 alpha-dihydrotestosterone) were more concentrated in the stroma, and that significant correlations between concentrations of metabolically related androgens were more common in the stroma than in the epithelium, indicate that the stroma is an important site of androgen metabolism in benign prostatic hypertrophic tissues. The present data also support the suggestion that 5 alpha-dihydrotestosterone produced in the prostatic stroma may be transferred to the epithelium by way of sex hormone binding globulin in the extracellular spaces of the prostate.

Steroid monosulphate and disulphate fractions were obtained from human faeces by chromatography on Sephadex LH-20 and solvolysed. The steroids liberated were fractionated on silicic acid. Fractions containing C19O2 and C21O2 steroids were studied by thin-layer chromatography, gas-liquid chromatography and gas chromatography-mass spectrometry. Dehydroepiandrosterone, 5α-androstane-3α,17α-diol, 5α-androstane-3α,17β-diol, 5α-androstane3β,17α-diol, 5α-androstane-3β,17β-diol, 5β-androstane-3α,17β-diol, 5-androstene-3α,17β-diol, 5-androstene-3β,17α-diol, 5-androstene-3β,17β-diol, 5α-pregnane-3α,20α-diol, 5α-pregnane-3β,20αdiol, 5β-pregnane-3α,20α-diol, 5β-pregnane-3β,20α-diol,pregnenolone, 5-pregnene-3α,20α-diol and 5-pregnene-3β,20α-diol were found in the monosulphate fraction and 5-androstene-3β,17αdiol as well as 5-androstene-3β,17β-diol in the disulphate fraction of human faeces. Several steroids identified earlier in the disulphate fraction of human bric were found in the monosulphate fraction of human faeces, indicating partial hydrolysis of diconjugates in the intestine. The androstanediols and pregnanediols found m the faeces were primarily of a 3β-hydroxy-5α- or 3β-hydroxy-5β-structure, whereas those in the bile were of a 3α-hydroxy-5α- or 3α-hydroxy-5β-structure. This suggests conversion of a 3α-hydroxyl to a 3β-hydroxyl in the intestine in vivo. [ABSTRACT FROM AUTHOR]