title: In vitro metabolism of [4-14C] androstenedione and [4-14C] testosterone by rabbit placenta.
abstract: The metabolism of labelled androstenedione and testosterone in rabbit placenta on day 15 and 28 of gestation was studied in vitro. Extensive ring A reduction was observed. 5beta-Androstane-3alpha,17beta-diol,5beta-androstane-3beta,17beta-diol, 3alpha-hydroxy-5beta-androstan-17-one, 3beta-hydroxy-5beta-androstane-17-one, 17beta-hydroxy-5beta-androstan-3-one and 5beta-androstane-3, 17-dione were formed from androstenedione as proved by crystallization method. Testosterone was metabolized to 5beta-androstane-3alpha,17beta-diol, 5beta-androstane-3beta,17beta-diol and 17beta-hydroxy-5beta-androstan-3-one. The formation of estrogens was not found from any precursor. The results indicate that the rabbit placenta in the mid and late gestation shows delta4-5beta-reductase, 17beta-, 3alpha-and 3beta-hydroxysteroid dehydrogenase activities.
mesh_terms: D000735:Androstenedione / Q000378:metabolism*; D000818:Animals; D002250:Carbon Radioisotopes; D002265:Carboxylic Ester Hydrolases; D005260:Female; D005865:Gestational Age; D066298:In Vitro Techniques; D010088:Oxidoreductases / Q000378:metabolism; D010920:Placenta / Q000201:enzymology / Q000378:metabolism*; D011247:Pregnancy; D011817:Rabbits; D013739:Testosterone / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D013739:Testosterone; D000735:Androstenedione; D010088:Oxidoreductases; D002265:Carboxylic Ester Hydrolases