Marchut M
Endocrinol Exp. 1977;11(2):139-46.
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.
对妊娠第15天和28天兔胎盘中标记的雄烯二酮和睾酮的代谢进行了体外研究。观察到广泛的A环还原。通过结晶法证明,雄烯二酮可生成5β-雄烷-3α,17β-二醇、5β-雄烷-3β,17β-二醇、3α-羟基-5β-雄甾-17-酮、3β-羟基-5β-雄甾-17-酮、17β-羟基-5β-雄甾-3-酮和5β-雄烷-3,17-二酮。睾酮代谢生成5β-雄烷-3α,17β-二醇、5β-雄烷-3β,17β-二醇和17β-羟基-5β-雄甾-3-酮。未发现任何前体生成雌激素。结果表明,妊娠中期和晚期的兔胎盘具有Δ4-5β-还原酶、17β-、3α-和3β-羟基类固醇脱氢酶活性。