Biotransformation of testosterone and other androgens by suspension cultures of Nicotiana tabacum “Bright yellow”

It has been shown that the cultured cells of Nicotiana tabacum “Bright Yellow” are capable of transforming testosterone to Δ⁴-androstene-3, 17-dione, 5α-androstan-17β-ol-3-one, 5α-androstane-3β, 17β-diol, its dipalmitate and 3- and 17-monoglucosides, epiandrosterone, its palmitate and glucoside, testosterone glucoside. 5α-Androstane-3β, 17β-diol dipalmitate and 3- and 17-monoglucosides, epiandrosterone palmitate and glucoside, and testosterone glucoside have been found for the first time as metabolites of testosterone in plant systems. Δ⁴-Androstene-3,17-dione was converted to testosterone. 5α-Androstan-17β-ol-3-one, which has been recognized as an active form of testosterone in mammals, was also detected. It has also been demonstrated that [4-¹⁴C]testosterone is actively incorporated in these transformations.     

Determination of estriol, estriol sulfate, progesterone and neutral steroid mono- and disulfates in umbilical cord blood plasma

Fractions of unconjugated steroids, and steroid mono- and disulfates were isolated from cord plasma, and the concentrations of estriol, estriol sulfate, progesterone, 13 neutral steroid monosulfates (MoS) and 10 neutral steroid disulfates (DiS) were determined by gas-liquid chromatography. The mean concentrations in 30 cord plasma samples at term after normal pregnancy and delivery were as follows (μg/100 ml of free steroid ±standard deviation): estriol 16±5; estriol monosulfate 135±43; progesterone 59±19; dehydroepiandrosterone MoS 76±23; 5-androstene-3_β,17_α-diol DiS 279±77; 5-androstene-3_β,17_β-diol DiS 211±109; 16_α-hydroxydehydroepiandrosterone MoS 305±97; 16_β-hydroxy-dehydroepiandrosterone DiS 8±25; 33,17_β-dihydroxy-5-androsten-16-one MoS 37±16, DiS 29±15 5-androstene-3_β,16_α,17_β-triol MoS 25±9; 5-androstene-3_β,16_β,17_α-triol DiS 31±14; pregnenolone MoS 4±33; 5-pregnene-3_β,20_α-diol MoS 41±14, DiS 68±43; 16_α-hydroxypregnenolone MoS 101±42; 17-hydroxypregnenolone MoS 56±30; 21-hydroxypregnenolone DiS 26±15; 5-pregnene-3_β,20_α,21-triol MoS 37±18; 5_α-pregnane-3_α,20_α-diol MoS 21±10, DiS 54±21; 5_α-pregnane-3_β,20_α-diol MoS 18±9, DiS 7±39; 5_β-pregnane-3_α,20_α-diol MoS 17±7; 5_α-pregnane-3_α,20_α,21-triol MoS 110±56, DiS 22±19.The total amount of steroid monosulfates in the cord plasma pool was 1 mg/100 ml and that of steroid disulfates 0.5 mg/100 ml. 3_β-Hydroxy-Δ⁵-steroids predominated. Considerable amounts of saturated c₂₁ steroids were also detected. No statistically significant differences were found in the concentrations of any of the steroids studied, when a group of male and female fetuses were compared.     

Feminization of hepatic S metabolism in male rats with a transplanted (MtT/F4)

After transplantation of MIT/F₄ pituitary tumor cells to male rats of the Fisher strain, the masculine type of hepatic steroid metabolism was changed into a feminine pattern of enzyme activities. Liver metabolism of steroid hormones in female rats was relatively unaffected following transplantation of pituitary tumor cells. Furthermore, extract from MIT/F₄ tumors and “autonomous” pituitary tissue increased the 5α-reductase activity of hepatoma cells in the culture (HTC cells) at subsaturation concentrations of the substrate 4-androstene-3, 17-dione by decreasing the apparent K_m of the enzyme. It is concluded that the pituitary tumor (in accord with the secretion from an “autonomous” pituitary gland) secretes “feminotropin,” a novel hypophyseal principle that probably is an important regulator of hepatic steroid metabolism. It is suggested that pituitary tumor tissue of the MtT/F₄ type could be used as source of feminotropin in purification studies.     

Steroids in newborns and infants identification by combined gas chromatography-mass spectrometry of the major steroids excreted by a newborn chimpanzee (Pan troglodytes)

The following steroids have been identified by combined gas chromatography-mass spectrometry in a urine specimen collected from a newborn chimpanzee; 5-androstene-3β, 17α-diol, 3β,16α (and 16β)-dihydroxy-5-androsten-17-one, 5-androstene-3β, 16α, 17β-triol, 5-androstene-3β, 16β, 17α-triol, 5-pregnene-3β, 20α-diol, 5-pregnene-3β, 20α, 21-triol, 3β,21-dihydroxy-5-pregnen-20-one, 3β, 16α-dihydroxy-5-pregnen-20-one, 5-Piegnene-3β, 16α,20α, 21-tetrol, 5-pregnene-3β,17α, 20ξ, 21-tetrol androstenetriolones and androstenetetrols.     

Androgen metabolism by rat epididymis. 1. Metabolic conversion of 3 H-testosterone in vivo

The epididymis of adult rats metabolize ³H-testosterone by experiments $\text{in vivo}$. Thirty minutes after the injection of 100 μCi ³H-testosterone, some 10 per cent of the total radioactivity of the epididymis was found in the water-soluble fraction, whereas 90 per cent was found in the ether soluble fraction (free steroids). The free steroids were examined further and the following androgenic metabolites identified: $\text{testosterone}$ (17β-hydroxy-4-androsten-3-one) 8, 9%, $\text{androstendipne}$ (4-androstene-3, 17-dione, 2,7%,$\text{5α-A-dione}$ (5α-androstane-3, 17-dione) 6,5%, $\text{DHT}$ (17β-hydroxy-5α-androstan-3-one) 47, 2%, $\text{3β-diol}$ (5α-androstane-3β, 17β-diol) 4, 4%, $\text{3α-diol}$ (5α-androstane-3α,17β-diol) 20, 8% and $\text{androsterone}$ (3α-hydroxy-5α-androstan-3-one) 3,4%. The relative amount of each metabolite is given in per cent of total radioactivity in the ether soluble fraction.     

One step synthesis of 6-oxo-cholestan-3β,5α-diol

Cholesterol metabolism has been recently linked to cancer, highlighting the importance of the characterization of new metabolic pathways in the sterol series. One of these pathways is centered on cholesterol-5,6-epoxides (5,6-ECs). 5,6-ECs can either generate dendrogenin A, a tumor suppressor present in healthy mammalian tissues, or the carcinogenic cholestane-3β,5α,6β-triol (CT) and its putative metabolite 6-oxo-cholestan-3β,5α-diol (OCDO) in tumor cells. We are currently investigating the identification of the enzyme involved in OCDO biosynthesis, which would be highly facilitated by the use of commercially unavailable [¹⁴C]-cholestane-3β,5α,6β-triol and [¹⁴C]-6-oxo-cholestan-3β,5α-diol. In the present study we report the one-step synthesis of [¹⁴C]-cholestane-3β,5α,6β-triol and [¹⁴C]-6-oxo-cholestan-3β,5α-diol by oxidation of [¹⁴C]-cholesterol with iodide metaperiodate (HIO₄).     

Formation of 5α-dihydrotestosterone from 5α-androstane-3α,17β-diol in prostate cancer LAPC-4 cells – Identifying inhibitors of non-classical pathways producing the most potent androgen

5α-Dihydrotestosterone (5α-DHT) possesses a great affinity for the androgen receptor (AR), and its binding to AR promotes the proliferation of prostate cancer (PC) cells in androgen-dependent PC. Primarily synthesized from testosterone (T) in testis, 5α-DHT could also be produced from 5α-androstane-3α,17β-diol (3α-diol), an almost inactive androgen, following non-classical pathways. We reported the chemical synthesis of non-commercially available [4-¹⁴C]-3α-diol from [4-¹⁴C]-T, and the development of a biological assay to identify inhibitors of the 5α-DHT formation from radiolabeled 3α-diol in LAPC-4 cell PC model. We measured the inhibitory potency of 5α-androstane derivatives against the formation of 5α-DHT, and inhibition curves were obtained for the most potent compounds (IC₅₀ = 1.2–14.1 μM). The most potent inhibitor 25 (IC₅₀ = 1.2 μM) possesses a 4-(4-CF₃-3-CH₃O-benzyl)piperazinyl methyl side chain at C3β and 17β-OH/17α-CCH functionalities at C17 of a 5α-androstane core.     

Steroid metabolism by mouse submaxillary glands. I. in vitro metabolism of testosterone and 4-androstene-3,17-dione

Tritiated 4-androstene-3,17-dione and testosterone were incubated with submaxillary gland homogenates of 6 month old male mice. In 15 and 180 minute incubations fortified with NADPH, submaxillary tissue converted 4-androstene-3,17-dione predominantly to androsterone and, to a lesser extent, testosterone, 17β-hydroxy-5α-androstan-3-one and 5α-androstane-3α, 17β-diol. Testosterone was converted primarily to 5α-androstane-3α, 17β-diol when exogenous NADPH was available; trace amounts of 4-androstene-3,17-dione, 17β-hydroxy-5α-androstan-3-one and androsterone were also formed. When a NADPH-generating system was omitted from the incubation medium both 4-androstene-3,17-dione and testosterone were poorly metabolized by submaxillary tissue; the amounts of reduced metabolites accumulating were markedly reduced.     

Androgen metabolism by rat epididymis. 2. Metabolic conversion of 3H-testosterone in vitro

The epididymis of adult rats metabolizes ³H-testosterone by experiments $\text{in}$$\text{vitro}$. After incubation of slices from epididymal tissue for 2 hrs at 37°C, 8% of the total radioactivity was found in the water-soluble fraction, whereas 92% in the ether soluble fraction (free steroids). The free steroids were examined further and the following metabolites identified: $\text{testosterone}$ (17β-hydroxy-4-androsten-3-one) 10,4%, $\text{androstendione}$ (4-androstene-3,17-dione) 6,2%, $\text{5α-A-dione}$ (5α-androstane-3,17-dione) 7,3%, $\text{DHT}$ (17β-hydroxy-5α-androstane-3-one) 39,3%, $\text{3α-diol}$ (5α-androstane-3α,17β-diol) 22,7%, $\text{3β-diol}$ (5α-androstane-3β,17β-diol) 4,6% and androsterone(3α-hydroxy-5α-androstan-17-one) 8,9%. The relative amount of each metabolite is given in per cent of the total radioactivity in the ether soluble fraction. When segments (caput, corpus, cauda) of epididymis were incubated in the same way, differences in steroid metabolism were demonstrated. Characteristic for caput epididymidis was high formation of DHT (58,4%) and 3α-diol (23,5%). Corpus epididymidis showed lower formation of DHT (50,6%) and 3α-diol (12,7%), but an approximately 3 times higher formation of 5α-A-dione (12,0%) than caput (3,4%) and cauda (3,5%). Cauda epididymis showed the lowest formation of DHT (38,3%), whereas 3α-diol (29,1%) and androsterone (11,4%) formation were relatively high. The ratio between 17β-hydroxy metabolites (DHT and androstanediols) and 17-keto metabolites were much higher in the caput (8,8) than in the corpus (3,2) and cauda (3,6), indicating a higher 5α-reductase activity in this segment.     

Androgen regulation of progestin biosynthetic enzymes in FSH-treated rat granulosa cells in vitro

The influence of androgens on the FSH modulation of progestin biosynthetic enzymes was studied $\text{in vitro}$. Granulosa cells obtained from immature, hypophysectomized, estrogen-treated rats were cultured for 3 days in a serum-free medium containing FSH (20 ng/ml) with or without increasing concentrations (10^?9?10^?6 M) of 17β-hydroxy-5α-androstan-3-one (dihydrotestosterone; DHT), 5α-androstane-3α, 17β-diol (3α-diol), or the synthetic androgen 17β-hydroxy-17-methyl-4,9,11-estratrien-3-one (methyltrienolone; R1881). FSH treatment increased progesterone and 20α-hydroxy-4-pregnen-3-one(20α-OH-P) production by 10.2- and 11-fold, respectively. Concurrent androgen treatment augmented FSH-stimulated progesterone and 20α-OH-P production in a dose-related manner (R1881 > 3α-diol > DHT). In the presence of an inhibitor of 3β-hydroxysteroid dehydrogenase (3β-HSD), the FSH-stimulated pregnenolone (3β-hydroxy-5-pregnen-20-one) production (a 20-fold increase) was further enhanced by co-treatment with R1881, 3α-diol or DHT. Furthermore, FSH treatment increased 4.4-fold the activity of 3β-HSD, which converts pregnenolone to progesterone. This stimulatory action of FSH was further augmented by concurrent androgen treatment. In contrast, androgen treatment did not affect FSH-stimulated activity of a progesterone breakdown enzyme, 20α-hydroxysteroid dehydrogenase(20α-HSD). These results demonstrate that the augmenting effect of androgens upon FSH-stimulated progesterone biosynthesis is not due to changes in the conversion of progesterone to 20α-OH-P, but involves an enhancing action upon 3β-HSDΔ⁵, Δ⁴-isomerase complexes and additional enzymes prior to pregnenolone biosynthesis.     

In vivo MRI evaluation of anabolic steroid precursor growth effects in a guinea pig model

Anabolic steroids are widely used to increase skeletal muscle (SM) mass and improve physical performance. Some dietary supplements also include potent steroid precursors or active steroid analogs such as nandrolone. Our previous study reported the anabolic steroid effects on SM in a castrated guinea pig model with SM measured using a highly quantitative magnetic resonance imaging (MRI) protocol. The aim of the current study was to apply this animal model and in vivo MRI protocol to evaluate the growth effects of four widely used over-the-counter testosterone and nandrolone precursors: 4-androstene-3 17-dione (androstenedione), 4-androstene-3β 17β-diol (4-androsdiol), 19-nor-4-androstene-3β-17β-diol (bolandiol) and 19-nor-4-androstene-3 17-dione (19-norandrostenedione). The results showed that providing precursor to castrated male guinea pigs led to plasma steroid levels sufficient to maintain normal SM growth. The anabolic growth effects of these specific precursors on individual and total muscle volumes, sexual organs, and total adipose tissue over a 10-week treatment period, in comparison with those in the respective positive control testosterone and nandrolone groups, were documented quantitatively by MRI.     

Biliary metabolites of testosterone and testosterone glucosiduronate in the rat

A mixture of testosterone-4-¹⁴C and testosterone-1,2-³H-17-glucosiduronate was intraperitoneally administered into male and female rats with bile fistulas. Biliary metabolites were separated and purififd by a combination of column chromatography, enzymic hydrolysis or solvolysis of the conjugate fractions and identification of the liberated aglycones. The injected steroids were extensively metabolized and excreted predominantly in the blue. 5β-Androstane-3α, 17β-diol was found principally in monoglucosiduronate fraction and was produced preferentially from the injected conjugate in both sexes. Very marked sex differences from the injected conjugate in both sexes. Very marked sex differences were observed in the following metabolites: Androsterone was present only in the female as monoglucosidironate, which was preferentially derived from testosterone. 5α-Androstane-3α,17β-diol was identified in both monoglucosiduronate and diconjugate fractions of the female, which was formed significanrly more from the conjugate than testosterone. These findings provide evidence that testosterone glucosiduronate could be converted directly into 5α-steroids as well as 5β-ones $\text{in}$$\text{vivo}$. In marked contrast, the major portion of testosterone was metabolized to polar steroids in the male.     

Steroid metabolism by purified adult rat leydig cells in primary culture

To characterize Leydig cell steroidogensis, we examined the metabolism of (³H)pregnenolone (3β-hydroxy-5-pregnen-20-one) to androgens in the presence and absence of human chorionic gonadotropin (hCG) as a function of culture duration. Approximately 20–30% of the (³H)pregnenolone was converted to testosterone (17_β-hydroxy-4-androsten-3-one) by purified Leydig cells at 0, 3 and 5 days (d) of culture. Androstenedione (4-androstene-3,17-dione) and dihydrotestosterone (17_β-hydroxy-5_α-androstan-3-one) were also produced while on day 5 of culture, significant amounts of progesterone (4-pregnene-3, 20-dione) were isolated. The Δ⁵ intermediates, 17-hydroxypregnenolone (3β, 17-dihydroxy-5-pregnen-20-one) and dehydroepiandrosterone (3β-hydroxy-5-androsten-17-one), accounted for less than 1% of substrate conversion, indicating a clear preference for Leydig cells to metabolize (³H)pregnenolone via the Δ⁴ pathway. On day 0 of culture, unidentified metabolites consisted of predominately polar steroids while on day 5 of culture, the unidentified metabolites consisted of predominately nonpolar steroids. In the presence of hCG, (³H)pregnenolone metabolism did not differ from basal on day 0 or 3 of culture. HCG increased the conversion of pregnenolone to progesterone and 17-hydroxyprogesterone (17-hydroxy-4-pregnene-3, 20-dione) on 5d. This suggests that Leydig cells cultured for 5d have decreased C_17–20 desmolase activity or that hCG acutely stimulates 3β-hydroxysteroid dehydrogenase and Δ⁴-Δ⁵ isomerase activities.     

Comparative placental steroid synthesis. II. C19 steroid metabolism by guinea-pig placentas and fetal adrenals in vitro

Placental homogenates from guinea-pigs at 16, 20, 35 and 55 days gestation were incubated with 7α-³H-dehydroepiandrosterone and 4-¹⁴C-androstenedione and analyzed for conversion products by reverse isotope dilution methods. ¹⁴C-3α-Hydroxy-5α-androstan-17-one, ¹⁴C-androstane-3α, 17β-diol and ³Handrost-5-ene-3β, 17β-diol were isolated from homogenates incubated with substrates for 2 hours. ³H, ¹⁴C-Testosterone was isolated from preparations incubated for 15 minutes or with high substrate: tissue ratios. Androst-4-ene-3, 17-dione, 5α-androstane-3, 17-dione, 5β-androstanedione derivative and C₁₈ steroid formation could not be demonstrated. These results demonstrate the capacity of guinea-pig placentas to convert dehydroepiandrosterone and androstenedione to testosterone and to derivatives reduced in ring A (5α) and at carbon 17. The activity of the Δ⁵-3β-hydroxysteroid dehydrogenase enzyme system appears to have been rate limiting.Homogenates of adrenals from 44–55 day old fetuses converted 4-¹⁴C-pregnenolone to androst-4-ene-3, 17-dione and 6β- and 11β-hydroxyandrostenedione. A guineapig fetal-placental unit is postulated, with steroid metabolic characteristics different from the human unit. Both permit reduction of fetal adrenal cortisol production and placental removal of C₁₉ steroids.     

Identification by capillary gas chromatography-mass spectrometry of eleven non-ecdysteroid steroids in the haemolymph of larvae of Sarcophaga bullata

$\text{O-}\text{Pentafluorobenzyloxime}$ (OPFB)-heptafluorobutyrylester (HFB) derivatives and $\text{OPFB}\text{-O-}\text{methyloxime}$ (MO)-trimethylsilylether (TMS) derivatives of non-ecdysteroid steroids were prepared from haemolymph extracts of last instar larvae of the fleshfly Sarcophaga bullata. Using a negative ion chemical ionization capillary gas chromatography-mass spectrometry (NCI/GC-MS) technique the following steroids could be identified: progesterone, testosterone, 5α-androstane-3β,17β-diol, 5β-androstane-3α,17β-diol, androst-5-ene-3β,17β-diol, androstenedione, 5α-dihydrotestosterone, 11-ketotestosterone, 11β-hydroxytestosterone, 17α-hydroxyprogesterone, 17α-hydroxyprogesterone, 17α,20β-dihydroxyprogesterone. Although the technique is very sensitive, estrogens could not be detected. These results suggest an active metabolism of progesterone and testosterone.     

Comparative C19-radiosteroid metabolism by MA 160 and HeLa cell lines

Summary Since the designation of the human MA 160 line as prostatic epithelial cells has been questioned and the possibility of HeLa cross contamination raised, this comparative study of C₁₉-radiosteroid transformation in MA 160 and HeLa monolayer cultures was done to determine whether these cells possess the distinguishing features of reductive and oxidative androgen metabolism expected in male and female genital organs, respectively. We compared the radiometabolite patterns produced by incubating [¹⁴C]testosterone (300nM) and [³H]testosterone (3nm) and 5α-dihydrotestosterone (17β-hydroxy-5α-androstan-3-one) with cultures of prostatic MA 160 and HeLa Parent, TCRC-1, TCRC-2 and ATC 229 cells. C₁₉-Radiosteroid metabolite patterns from MA 160 cell incubations also were compared with patterns generated by MA 196 fibroblasts from abdomnal skin of the same donor. MA 160 cells metabolized radiotestosterone predominantly to 5α-dihydrotestosterone, 5α-androstane-3α,17β-diol and 5α-androstane-3β,17β-diol. The diol epimers were the principal metabolites of 5α-dihydrotestosterone radiosubstrate. In contrast, radiotestosterone metabolism by MA 196 and HeLa Parent, TCRC-1 and TCRC-2 cells was overwhelmingly to the 17-oxosteroids 4-androstene-3,17-dione and androsterone. Another pathway was operative in HeLa 229 and, to a minor extent, in TCRC-1, which converted radiotestosterone to 4-androstene-3α,17β-diol and 5α-androstane-3α,17β-dol, with little formation of 5α-dihydrotestosterone. MA 160 cells thus metabolize radiotestosterone preponderantly to 5α-reduced 17β-hydroxysteroids as expected for prostatic epithelial cells, whereas HeLa cells show heterogeneity in metabolizing the labeled hormone by the alternative 17-oxosteroid and Δ⁴ pathways. This work was supported by Public Health Service Research Grants CA 13417 and CA 12924 from the National Cancer Institute, AM 11011 from the National Institute of Arthritis, Metabolism and Digestive Diseases, and by appropriations of the Commonwealth of Massachusetts, Item No. 4532-9003-01.     

Androgen glucuronides: I. Direct formation in rat accessory sex organs

A simple one-step procedure is described on the isolation of androgen glucuronides from various rat tissues. This procedure uses polyacrylamide gel electrophoresis, and permits a quantitative isolation of a single band containing the total androgen glucuronides without the contamination of free androgens and androgen sulfates. This procedure was used to determine the ability of various tissues of the rat to form androgen glucuronides directly when they were incubated with 1,2-[³H]-testosterone (0.1 μM) $\text{in}$$\text{vitro}$. Of eleven organs studied, only the accessory sex organs (ventral prostate, seminal vesicle, and coagulating gland), liver, and kidney were capable of forming androgen glucuronides. At the end of a one-hour incubation period, approximately 1% of the total radiolabeled steroids in the prostatic tissue minces were in the form of glucuronide conjugates. The predominant androgen glucuronide formed in the accessory sex organs was 5α-androstane-3α,17β-diol 17β-d-glucuronide. This is in contrast to the rat liver and kidney in which testosterone glucuronide was the predominant conjugate.A similar amount of labeled glucuronide conjugates was formed from either [³H]-testosterone, [³H]-dihydrotestosterone or [³H]-androstenedione, whereas negligible amount of steroid conjugates was formed from [³H]-cortisol. The formation of androgen glucuronides requires metabolically active tissues; furthermore, the conjugation process was inhibited by the antiandrogen, cyproterone acetate, or by metabolic inhibitors, such as oligomycin or N-ethylmaleimide.     

A simple method for the assay of eight steroids in small volumes of plasma

A simple method is described for the simultaneous radioligand assay of four Δ⁵-3β-hydroxysteroids adjacent to one another on the biosynthetic pathway (pregnenolone [1], 17α-hydroxypregnenolone, dehydroepiandroste rone and 5-androsterone-3β,17β-diol), and their four Δ⁴-3keto products (progesterone, 17α-hydroxyprogesterone, 4-androstene-3, 17-dione and testosterone). Two plasma aliquots are extracted and fractionated each for four steroids and individual corrections are made for losses. For fractionation, maximum use is made of the high resolution and reproducibility of celite minicolumns, using propylene glycol as stationary phase, and a discontinuous gradient of ethyl acetate in iso-octane as mobile phase. The fractions are then assayed in the appropriate radioligand end-assay system. Each assay was finally validated by demonstrating coincidence of peaks of immuno- and radioactive steroid In extracts of female plasma. Results in pre-pubertal girls and women in the follicular phase of the menstrual cycle suggest that the major change in adrenal steroid production at puberty may be an increase in 17,20-desmolase activity. There appears to be little reversal of this change in adrenal function after ovariectomy.     

Sertoli cells from immature rats : in vitro stimulation of steroid metabolism by FSH.

Sertoli cells from 10 day old rats convert androstenedione to testosterone and 5α-androstane-3α,17β-diol, testosterone to 17β-hydroxy-5α-androstan-3-one and 5α-androstane-3α,17β-diol, and 17β-hydroxy-5α-androstan-3-one to 5α-andro-stane-3α,17β-diol after 72 hours $\text{in vitro}$. Conversions of androstenedione to testosterone and 5α-androstane-3α,17β-diol, and testosterone to 5α-androstane-3α,17β-diol were 2 to 3 times greater in FSH treated cultures. Steroid conversion was not stimulated significantly by LH or TSH. The results are interpreted as evidence that in young rats Sertoli steroid metabolism is stimulated by FSH, that Sertoli cells are an androgen target and that FSH may induce or facilitate Sertoli androgen responsiveness.     

Proton magnetic resonance spectra of 17ξ-Hydroxy-17ξ-methyl-5ξ-androstane C-3 ketone and c-3ξ alcohol isomers in chloroform-d and pyridine-d5

17α-Hydroxy-17β-methyl-5β-androstan-3-one, 17μ-methyl-5α-androstane-3α, 17α-diol, 17β-methyl-5α-androstane-3β, 17α-diol, 17α-methyl-5β-androstane-3β, 17β-diol, 17β-methyl-5β-androstane-3α, 17α-diol and 17β-methy1–5β-androstane-3β, 17α-diol were synthesized for the first time. ¹H NMR spectra of all four 17ξ-hydroxy/17ξ-methyl C-3 ketones and all eight C-3 alcohols were recorded in chloroform-d and pyridine-d₅. Pyridine-induced chemical shifts are discussed. Thin-layer Chromatographic data are given.