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At least 19 recordsLinked to original sources
PubMed1979

Metabolism of 5 alpha-androstane-3 beta,17 beta-diol to 17 beta-hydroxy-5 alpha-androstan-3-one and 5 alpha-androstan-3 alpha,17 beta-diol in the rat.

Significant metabolism of 5 alpha-androstane-3 beta,17 beta-diol to 17 beta-hydroxy-5 alpha-androstan-3-one was recorded in several tissues and organs from rats and humans. This bioconversion was further investigated in rat testis homogenates. 5 alpha-Androstane-3 beta,17 beta-diol was readily metabolized to 17 beta-hydroxy-5 alpha-androstan-3-one with NAD and/or NADP added as cofactors. When a NADPH generating system was included in the incubation, 5 alpha-androstane-3 beta,17 beta-diol was metabolized to 5 alpha-androstan-3 alpha,17 beta-diol. Only small amounts of 17 beta-hydroxy-5 alpha-androstan-3-one accumulated under the latter condition.

Androstanols↗
PubMed1979

Pituitary metabolism of 5alpha-androstane-3beta-17beta-diol: intense and rapid conversion into 5alpha-androstane-3beta,6alpha,17beta-triol and 5alpha-androstane-3beta,7alpha, 17beta-triol.

In the male rat pituitary, 5alpha-androstane-3beta, 17beta-diol (3beta-diol) is extensively metabolized into polar steroids. They were identified as 5alpha-androstane-3beta, 6alpha-17beta-triol (6alpha-triol) and 5alpha-androstane-3beta, 7alpha, 17beta-triol (7alpha-triol). 6-alpha-Triol represents 53% and 7alpha-Triol 28% of the total 3beta-diol metabolites. The remaining percentage is related to 6beta and 7beta isomers. The biological role of triols is still unknown.

Androstane-3,17-diol↗
PubMed1979

Age-related changes in conversion of 5 alpha-androstan-17 beta-ol-3-one to 5 alpha-androstane-3 alpha,17 beta-diol and 5 alpha-androstane-3 beta,17 beta-diol by rat testicular cells in vitro.

Conversion of labelled 5 alpha-androstane-17 beta-ol-3-one (DHT) by isolated testicular cells from rats of different ages was examined under saturating substrate conditions in vitro (5--10 micrograms DHT/ml in a 24 h incubation). Two detectable metabolites of DHT were produced by testicular cells in vitro. 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-diol) and 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-diol). Production of these diols during a 24 h period was linear, and the amounts formed were directly related to the cell number. The amount of 3 alpha- and 3 beta-diols formed by testicular cells of rats of different ages increased from Day 10 to Day 25, then declined. Testicular cells from rats 10 to 20 days of age converted DHT mainly to 3 alpha-diol, but thereafter 3 beta-diol was the predominant testicular metabolite of DHT.

Aging↗
PubMed1979

Metabolism and binding in vitro of 5 alpha-androstane-3 beta, 17 beta-diol and of 5 alpha-androstane-3 alpha, 17 beta-diol in cell fractions of rat ventral prostate and liver.

Rat ventral prostate and liver were investigated for the binding in vitro to particulate fractions and for the metabolism of 5 alpha-androstane-3 beta, 17 beta-diol. Comparative investigations were carried out on the metabolism of 5 alpha-androstane-3 alpha, 17 beta-diol. Preparations of the liver were investigated in order to establish the organ specificity of the method. In the prostate, the bulk of the metabolites of 5 alpha-androstane-3 beta, 17 beta-diol was present as steroids of high polarity. Of the less polar metabolites, 17 beta-hydroxy-5 alpha-androstan-3-one, 3 beta-hydroxy-5 alpha-androstan, 17-one and 5 alpha-androstane-3 alpha, 17 beta-diol were detectable. The binding of a 5 alpha-androstane-3 beta, 17 beta-diol to mitochondria and microsomes was unspecific. In the liver, among the less polar metabolites, 3 beta-hydroxy-5 alpha-androstan-17-one was the main metabolite, and the binding was unspecific. The main metabolite in the prostate homogenate of 5 alpha-androstane-3 alpha, 17 beta-diol was 17 beta-hydroxy-5 alpha-androstan-3-one. The portion of highly polar steroids was very low. The portion of unmetabolized hormone was distributed almost equally among the different cell preparations except the nuclei, in which 17 beta-hydroxy-5 alpha-androstan-3-one was higher and 5 alpha-androstane-3 alpha, 17 beta-diol was lower than in the remaining cell fractions.

Androstane-3,17-diol↗
PubMed1975

Some factors affecting testosterone, dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3 beta,17 beta-diol secretion by invitro perfused rabbit testes.

Intra-arterial infusion of testosterone-3H gave rise to tritiated dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3beta,17 beta-diol in spermatic venous effluent of the perfused rabbit testis-epididymis. Mass spectrometric measurements confirmed that these four androgens were present in spermatic venous effluent of the perfused rabbit testis-epididymis. Gas liquid chromatographic measurement showed that testosterone, dihydrotestosterone, 5 alpha-androstan-3 alpha,17 beta-diol and 5 alpha-androstan-3 beta,17 beta-diol were secreted in similar amounts by the in vitro perfused and in situ rabbit testis-epididymis results obtained by perfusing the testis minus the epididymis suggested that the bulk of these androgens originate from the catabolism of testosterone within the testis rather than the epididymis. Suprisingly, germinal epithelium destruction by heat failed to alter the testosterone, dihydrotestosterone and 5 alpha-androstan-3 alpha,17 beta-diol secretion by the in vitro perfused rabbit testis. In contrast, the secretion of 5 alpha-androstan-3 beta,17 beta-diol was significantly (P less than 0.05) reduced in the same cryptorchid compared to control testes.

Androstane-3,17-diol↗
PubMed1977

Synthesis of new steroid haptens for radioimmunoassay. Part III. 15beta-Carboxyethylmercaptosteroid-bovine serum albumin conjugates. Specific antisera for radioimmunoassay of 5alpha-dihydrotestosterone, 5alpha-androstane-3beta, 17beta-diol and 5alpha-androstane-3alpha, 17beta-diol.

The syntheses of 15beta-carboxyethylmercapto-5alpha-dihydrotestosterone, 15beta-carbosyethylmercapto-5alpha-androstane-3beta, 17beta-diol and 15beta-carboxyethylmercapto-5alpha-androstane-3alpha, 17beta-diol and the preparation of their bovine serum albumin (BSA) conjugates are described. These conjugates were employed for the generation of specific antisera suitable for radioimmunoassay (RIA) of 5alpha-dihydrotestosterone (5alpha-DHT), 5alpha-androstane-3beta, 17beta-diol (3beta-diol) and 5alpha-androstane-3alpha, 17beta-diol (3alpha-diol).

Androstane-3,17-diol↗
PubMed1979

[Evidence of 5 alpha-androstane-3 beta, 6 alpha, 17 beta-triol and of 5 alpha-androstane-3 beta, 7 alpha, 17 beta-triol in the anterior pituitary of the prepuberal male rate].

Incubation of 3H-5 alpha-androstane-3 beta, 17 beta-diol with anterior pituitaries from immature male Rats led to the major production of polar radio-metabolites. Of these, 53 and 27% were identified with 5 alpha-androstane-3 beta, 6 alpha, 17 beta-triol and 5 alpha-androstane-3 beta, 7 alpha, 17 beta-triol, respectively. The formation of these trihydroxysteroids may be involved in the intracellular regulation of 5 alpha-androstane-3 beta, 17 beta-diol levels.

Androstane-3,17-diol↗
PubMed1977

Radioimmunoassays for androsterone, 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol.

Androsterone (3alpha-hydroxy-5alpha-androstan-17-one), 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol were conjugated at C-16 through sulfur to bovine and human serum albumin. Rabbits injected with these conjugates produced antibodies suitable for radioimmunoassays of these hormone metabolites. Samples were purified on Sephadex LH-20 columns. Levels of these steroids were measured in a rat blood serum pool and in ovarian tissue extract pools.

Androstane-3,17-diol↗
PubMed1979

Characterization of two new enzymatic activities of the rat ventral prostate: 5 alpha-androstane-3 beta, 17 beta-diol 6 alpha-hydroxylase and 5 alpha-androstane-3 beta, 17 beta-diol 7 alpha-hydroxylase.

This study has characterized two new enzymatic hydroxylase activities specific for 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-diol) in the rat ventral prostate: 5 alpha-androstane-3 beta, 17 beta-diol 6 alpha-hydroxylase (6 alpha-hydroxylase) and 5 alpha-androstane-3 beta, 17 beta-diol 7 alpha-hydroxylase (7 alpha-hydroxylase). Both of these irreversible hydroxylase activities require NADPH and are localized in the microsomal fraction of the prostate. The apparent Km for 3 beta-diol is 2.5 microM for both the 6 alpha- and 7 alpha-hydroxylase activities. The apparent Km for NADPH is 7.6 microM for the 6 alpha-hydroxylase and 7.0 microM for the 7 alpha-hydroxylase. The pH optimum for both activities is 7.4. Several steroid inhibitors of these hydroxylase activities in vitro were identified including cholesterol, progesterone, and estradiol. Estradiol was found in vitro to be a noncompetitive inhibitor (Ki = 5 microM). Injection of estradiol into intact male rats, simultaneously receiving exogenous testosterone, also produced a significant lowering of the 6 alpha-plus 7 alpha-hydroxylase activities. Both the 6 alpha- and 7 alpha-hydroxylase were found to be androgen sensitive. Following castration there is a rapid decrease in both activities.

Androstane-3,17-diol↗
PubMed1977

Simultaneous radioimmunoassay of tesosterone, dihydrotestosterone, 5 alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol in the plasms of adult male rats.

A single thin layer chromatography and three antibodies were used for the specific radioimmunoassay of four androgens in pooled rat plasma (Sprague-Dawley adult males). The following values were found (pg/ml +/- SD). Testosterone: 3, 138 +/-173; dihydrotestosterone: 374 +/-20; 5alpha-androstane-3alpha, 17beta-diol: 284+/-24; 5alpha-androstane-3beta, 17beta-diol: 223+/-11.

Androstane-3,17-diol↗
PubMed1977

Relative binding affinity of androstane and C-19-nor-androstane-steroids for the estradiol-receptor in human myometrial and mammary cancer tissue.

The relative binding affinity of several androstane- and C-19-nor-androstane-compounds for the estradiol (E2)-receptor in human myometrial and mammary cancer tissue was studied. High speed cytosol was incubated with tritiated E2 alone as well as in the presence of increasing amounts of the compound to be tested. The highest affinity is found for steroids with two hydroxyl-groups at C-3 and C-17 in the beta-position and a double bond at C-4-5 or C-5-6. Saturation of the A-ring decreases the affinity: 5alpha-compounds have less affinity, 5-beta-compounds have less affinity; 5beta-compounds hardly any affinity. The presence of a hydroxyl-group in the 3alpha, 11beta or 16beta-position decreases the affinity, as dose a 3-oxo or 17-oxo-group. Removal of the C-19-methyl-group facilitates the binding. This data led to the concept that flatness of the A-ring in respect to the B-ring of the steroid molecule is a principal requirement for binding to the E2-receptor. The rank order of RBA is identical in myometrium and in mammary cancer tissue, indicating that estrogen-receptors are at least highly similar in both target tissues.

Androstane-3,17-diol↗
PubMed1976

Interconversion between 17 beta-hydroxy-5alpha-androstan-3-one (5alpha-dihydrotestosterone) and 5alpha-androstane-3alpha, 17 beta-diol in rat kidney: heterogeneity of 3alpha-hydroxysteroid oxidoreductases.

3alpha-Hydroxysteroid oxidoreductases catalyzing the interconversion between 17 beta-hydroxy-5alpha-androstan-3-one (5alpha-dihydrotestosterone) and 5alpha-androstane-3alpha, 17 beta-diol (3alpha-androstanediol) have been studied in rat kidney. Three enzymes can be distinguished: a soluble NADPH-dependent oxidoreductase, a microsomal NADPH-dependent enzyme and a microsomal NADH-linked enzyme. Traces of the microsomal enzymes are consistently observed in the 108 000 X g supernatant. Studies on crude preparations reveal that these enzymes differ not only in subcellular localization and co-factor requirement, but also in optimum pH, kinetic characteristics, sensitivity to potential steroidal inhibitors and sensitivity to detergents, ionic strength and temperature. Moreover, salient sex differences exist in the activity of all three kidney enzymes. The soluble NADPH-dependent enzyme is more active in female rats whereas both microsomal enzymes are considerably more active in male animals. The microsomal NADH-dependent oxidoreductase displays favorable characteristics to catalyze the 3alpha-dehydrogenation of 3alpha-androstanediol. Evidence is presented that it is mainly this enzyme that enables the kidney to use 3alpha-androstanediol as an efficient precursor for the local formation of 5alpha-dihydrotestosterone.

Androstane-3,17-diol↗
PubMed1975

In vivo uptake and metabolism of 3-h-5alpha-androstane-3alpha,17beta-diol and of 3-h-5alpha-androstane-3beta,17beta-diol by human prostatic hypertrophy.

Tritiated 5alpha-androstane-3alpha,17beta-diol (3alpha-diol) and 5alpha-androstane-3beta,17beta-diol (3beta-diol) respectively were administered to patients with benign prostatic hypertrophy (bph) undergoing prostatectomy. In prostate and skeletal muscle homogenates and in plasma the total radioactivity content as well as the formation of metabolites were measured. Histological examination of each ectomized prostate was performed to evaluate the cellular composition of the tissue. After 3alpha-diol injection, a higher uptake of radioactivity in the prostate was obtained than after 3beta-diol. Within 30 min the 3alpha-isomer was very efficiently converted to 5alpha-DHT, while most of the 3beta-isomer remained unchanged. There was, however, also after administration of the 3beta-diol a substantial biconversion to 5alpha-DHT as has been confirmed by recrystallization to constant specific radioactivity. Only after 3beta-diol epiandrosterone was detected in small but significant amounts. 3alpha-diol administration resulted in distinct concentrations of 3beta-diol, whereas the conversion of 3beta-diol to the 3alpha-isomer was insignificant. When comparing the histological composition of the prostatic tissue with the accumulation of radioactivity and the formation of metabolites only a weak correlation between glandular structure and radioactivity uptake after 3alpha-diol administration could be revealed.

Aged↗
PubMedDate not supplied

Simultaneous radioimmunoassay of 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol unconjugated and conjugated in human serum.

The simultaneous determinations of both 3alpha and 3beta epimers of 5alpha-androstane-3,17beta-diol as their glucuronides, sulfates and in their unconjugated forms are described. The diol estimation is carried out by radioimmunoassay with two specific immune sera after purification of the serum by use of chromatography on Sephadex LH-20. The values obtained (mean +/- S.D.) in pg/ml for the unconjugated 3alpha and 3beta epimers were, respectively, 267 +/- 67 and 816 +/- 76 for men; 114 +/- 33 and 515 +/- 177 for women; 142+/- 77 and 779 +/- 200 for hirsute women. Among the conjugates, the most important were the sulfoconjugates, their rates being, respectively (men +/- S.D. in ng/ml 41.6 +/- 9.5 and 103+/- 40 for men; 12.4 +/- 3.1 and 51.2 +/- 14.9 for women and 36 +/- 22 and 72 +/- 36 for hirsute women. Differences in the conjugation of both epimers were also noticed.

Adolescent↗
PubMed1976

Effects of androstenes, 5alpha-androstanes, 5beta-androstanes, oestrenes and oestratrienes on serum gonadotrophin levels and ventral prostate weights in gonadectomized, adult male rats.

The morphologic and metabolic effect of a single intracutaneous injection of homologous endocrine pancreas in Freund's complete adjuvant (CFA) was studied in 100 mice and compared with control groups which had been (1) immunized with murine insulin in CFA, (2) injected with CFA alone, or had (3) received no treatment. There were no differences between the control groups as regards the morphology of the pancreatic islets, and the glucose tolerance was normal. Mice immunized with islet homogenate exhibited morphological changes in the form of degranulation and cytoplasmic disintegration. These changes involved B-cells as well as A2-cells and were present from 7 to 18 days after the immunization. A significant reduction in glucose tolerance was observed 14 days after the immunization. Another characteristic finding in the islets from the immunized mice was the extravascular presence of mononuclear, agranular cells which on the basis of their morphological criteria appeared to represent lymphocytes.

Androstanes↗