title: Identification of two 5alpha-reduced pregnanes as major metabolites of progesterone in immature rat ovaries (1000 x g supernatant) in vitro.
abstract: Incubation of the 1000 x g supernatant obtained from 23-day-old rat ovarian homogenate with labeled progesterone resulted in the production of 3 major metabolites; 5alpha-androstane-3alpha,17beta-diol, and two 5alpha-reduced pregnanes that were identified as 3alpha-hydroxy-5alpha-pregnan-20-one and 3alpha,17alpha-dihydroxy-5alpha-pregnan-20-one. The 3alpha,17alpha-dihydroxy-5alpha-pregnan-20-one has not been hitherto isolated from mammalian ovaries. The steroids were identified by their mobilities on thin-layer and gas-liquid chromatography, by mass spectroscopy, derivative formation and by recrystallization to constant specific activity. In another experiment, incubation of the 1000 x g supernatant from 23-day-old rat ovaries with 3alpha-hydroxy-5alpha-pregnan-20-one as substrate resulted in the production of 5alpha-androstane-3alpha,17beta-diol. It is suggested that 5alpha-androstane-3alpha,17beta-diol is produced in immature rat ovaries by a pathway in which the identified 5alpha-reduced pregnanes serve as intermediates.
mesh_terms: D015113:Androstane-3,17-diol / Q000096:biosynthesis / Q000378:metabolism; D000818:Animals; D005260:Female; D010053:Ovary / Q000254:growth & development / Q000378:metabolism*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D011276:Pregnanediol / Q000031:analogs & derivatives / Q000378:metabolism; D011278:Pregnanes / Q000378:metabolism*; D011280:Pregnanolone / Q000378:metabolism; D011374:Progesterone / Q000378:metabolism*; D051381:Rats
chemical_list: D011278:Pregnanes; D015113:Androstane-3,17-diol; D011374:Progesterone; D011280:Pregnanolone; D010088:Oxidoreductases; D011276:Pregnanediol