title: Biotransformation of pregnenolone - 7alpha-3H, progesterone - 7alpha-3H and dehydroepiandrosterone - 7alpha-3H by porcine fetal and maternal adrenal homogenate preparations.
abstract: The biotransformation of pregnenolone-7alpha-3H and of progesterone-7alpha-3H by porcine fetal and maternal adrenal homogenates at 56 and 112 days of pregnancy and of dehydroepiandrosterone-7alpha-3H by fetal adrenal homogenates has been investigated in vitro. Both pregnenolone-7alpha-3H and progesterone-7alpha-3H were metabolized extensively by maternal adrenal preparations, the principal radioactive metabolites isolated being cortisol, corticosterone, 11-deoxycortisol, deoxycorticosterone, 11beta-hydroxyprogesterone and androstenedione. In addition, 17alpha-hydroxyprogesterone, 20alpha-dihydroprogesterone and cortisone were formed from both substrates and 17alpha-hydroxypregnenolone and progesterone were formed from pregnenolone. Although essentially the same radioactive metabolites were isolated after incubation of fetal adrenal glands with pregnenolone-7alpha-3H or progesterone-7alpha-3H, a greater proportion of the radioactivity was associated with corticosteroids at 112 days of pregnancy than at 56 days. 11beta-Hydroxyandrostenedione and androstenedione were isolated and identified together with an unknown polar metabolite, after incubation of fetal adrenal tissue with dehydroepiandrosterone-7alpha-3H. These results are discussed in relation to feto-placental steroid biosynthesis and metabolism and the role of the fetal adrenal in the initiation of parturition in the pig.
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism*; D000818:Animals; D001711:Biotransformation; D003687:Dehydroepiandrosterone / Q000378:metabolism*; D005260:Female; D005333:Fetus / Q000378:metabolism*; D005865:Gestational Age; D066298:In Vitro Techniques; D011247:Pregnancy; D011270:Pregnancy, Animal; D011284:Pregnenolone / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism*; D013552:Swine
chemical_list: D003687:Dehydroepiandrosterone; D011374:Progesterone; D011284:Pregnenolone