New progesterone metabolites in human myometrium.

Homogenates from human myometrium with an added NADPH regenerating system and ATP were incubated with 4-(14)C progesterone. Six metabolites were identified: 5alpha-pregnane-3, 20-dione, 5beta-pregnane-3, 20-dione, 3alpha-hydroxy-4-pregnen-20-one, 3beta hydroxy-4-pregnen-20-one. 20alpha-hydroxy-4-pregnen-3-one and 20beta-hydroxy-4-pregnen-3-one. The identification of these metabolites was based on their behaviour in paper and thin layer chromatography and especially in radiogaschromatography either as free compounds or after formation of derivatives. The identification of the two allylic metabolites was supplemented by specific microchemical and enzymatic reactions. The formation of 5beta-pregnane-3, 20-dione, 20beta-hydroxy-4-pregnen-3-one and of the two allylic alcohols 3alpha-hydroxy-4-pregnen-20-one and 3beta-hydroxy-4-pregnen-20-one in human myometrium homogenates was demonstrated for the first time.

A simple radioimmunoassay for the measurement of testosterone glucosiduronate in unextracted urine.

A simple, reliable and rapid radioimmunoassay (RIA) for the determination of testosterone glucosiduronate (TG) in crude urine is described. Two protein-TG complexes were investigated in raising antibodies: a) Bovine serum albumin (BSA)-TG and b) human plasma Cohn's fraction IV-4 (CF)-TG. In rabbits, high titers of antibodies were obtained after the injection of CF-TG. The specificity of the antiserum was sufficiently high (cross reaction with free testosterone 27%, with 5alpha-dihydrotestosterone-glucosiduronate 20%). TG was estimated in small aliquots of male and female urine after evaporation overnight at 50 degrees C in order to eliminate interfering material. The intraassay coefficient of variation (CV) was found to be 6% and the interassay CV 11%. TB has been determined in 40 samples of urine simultaneously by "direct" RIA and by a "classical" RIA following hydrolysis with beta-glucuronidase. The coefficient of correlation was found to be 0.89. The mean excretion of TG in the urine of 26 healthy men amounted to 164+/-51 mug/24 hours with a range from 97 to 346 mug/24 hours. In a group of 16 women a mean urinary excretion of TG of 24+/-10 mug/24 hours was determined. The method allows a technician to assay 40 samples per day.

Gel chromatography of steroid oestrogens on sephadex LH-20.

The behavior of 23 steroid oestrogens Sephadex LH-20 using six solvent systems was investigated. The fractions eluted by gel column chromatography were analysed by thin-layer chromatography and spectrometry. The method was used for the radiochemical purity of labelled compounds by isotopic dilution.

Studies on the metabolism of steroids in the foetus. Biosynthesis of 6-alpha-hydroxytestosterone in the human foetal liver.

After incubation of testosterone with 105000g microsomes of human foetal liver, 6alpha-hydroxytestosterone was isolated and identified by t.l.c. and g.l.c.-mass spectrometry. This is the first example of 6alpha-hydroxylation of C(19) steroids in the human liver, and the finding is discussed in relation to earlier reports of 6-oxygenated C(19) and C(18) steroids in pregnant women.

Application of over-run thin-layer and gas-liquid chromatography in the separation of closely related C19O2 steroids.

An improved method for the separation of epimeric C19O2 steroids and their related allylic alcohols is described. In this method, the steroids are first separated by over-run thin-layer chromatography, and the unresolved groups are further analysed as free or as trimethylsilyl ether derivatives by gas-liquid chromatography. The behaviour of twenty-one C19O2 steroids was investigated by thin-layer chromatography in four systems and by gas-liquid chromatography in four liquid phases. All steroid pairs of similar polarity were resolved by the combination of these two fractionation procedures.

Metabolism of progesterone in uterine tissue of non-pregnant rats in vitro.

The metabolism of labelled progesterone was studied in vitro in uterine tissue of non-pregnant rats with particular emphasis on the influence of substrate concentration. Neither a qualitative nor quantitative difference was found for a steroid tissue ratio between 15 X 10(-6) and 4.2 X 10(-9) to 1 g (substrate amounts between 57.73 and 0.02 nmol); with both concentrations 42 to 44 per cent of progesterone was metabolized to about 35 per cent monohydroxymonoketonic steroids and 4-6 per cent dihydroxylated C21O2-compounds. In both sets of incubations we have isolated and identified the following steroids: 3alpha-hydroxy-5alpha-pregnan-20-one, 3beta-hydroxy-4-pregnen-20-one, 3alpha-hydroxy-4-pregnen-20-one, 20alpha-hydroxy-4-pregnen-3-one, 5alpha-pregnane-3alpha,20alpha-diol and 4-pregnene-3alpha,20alpha-diol. The most abundant metabolite formed in these incubations was 3alpha-hydroxy-4-pregnen-20-one which corresponds to about 30 per cent of the total activity recovered. It is the first time that the presence of 20alpha-hydroxysteroid-oxidoreductase activity is definitely established in this type of tissue. The identification of three allylic alcohols as progesterone metabolites in the rat uterus confirms that delta4-3-hydroxysteroids are important intermediates in the in vitro uterine metabolism of steroids.

Metabolism of 20beta-hydroxy-4-pregnen-3-one in uterine tissue of non-pregnant rats in vitro.

In vitro experiments carried out with uterus preparations of ovariectomized adult rats indicate the presence in this tissue of a 20beta-hydroxy-steroid-oxidoreductase which catalyzes the conversion of 20beta-hydroxy-4-pregnen-3-one to progesterone. Since a hepatic 20beta-hydroxysteroid-oxidoreductase is absent in adult female rats, the myometrial enzyme can be responsible for the biological activity of 20beta-hydroxy-4-pregnen-3-one in these animals. Besides progesterone five metabolites were isolated and identified after incubation of [4-14C]20beta-hydroxy-4-pregnen-3-one with uterine tissue: 20beta-hydroxy-5alpha-pregnan-3-one, 20beta-hydroxy-5beta-pregnan-3-one, 5alpha-pregnane-3alpha,20beta-diol, 4-pregnene-3alpha,20beta-diol and 4-pregnene-3beta,20beta-diol. The conversion of 20beta-hydroxy-4-pregnen-3-one to progesterone permits us to regard all five steroids isolated as progesterone metabolites in the rat uterus. 20beta-hydroxy-5beta-pregnan-3-one is the first C21-metabolite with a 5beta(H)-configuration isolated in the rat uterus, which indicates the presence of 5beta-reductase in this tissue.

Steroid metabolism in an androblastoma (Sertoli-Leydig cell tumor): a histopathological and biochemical study.

Steroidogenesis in a histologically and ultrastructurally clearly defined Sertoli-Leydig cell tumor ( androblastoma ) was studied by incubation of tumor slices with tritiated and unlabeled pregnenolone. Metabolites were isolated by thin-layer and gel-column chromatography and identified by gas chromatography associated with a radioactivity detector and/or by gas chromatography-mass spectrometry. Steroids were detected by mass chromatography as the trimethylsilyl- or tert-butyldimethylsilyl ethers. The following steroids were found: progesterone, 20 alpha-dihydroprogesterone, 17 alpha-hydroxypregnenolone, 5-pregnene-3 beta,20 alpha-diol, 4-androstene-3,17-dione, dehydroepiandrosterone, testosterone, androsterone, and etiocholanolone. The two latter C19-steroids were found to be the principal metabolites. Neither estradiol-17 beta nor estrone were detected. There was evidence from ultramicroscopic studies that in addition to typical Leydig cells, neoplastic stromal and sex cord cells are involved in androgen metabolism.