[Delta 5-3 beta hydroxysteroid dehydrogenase activity in the human full term placenta after culture: the effect of chorionic gonatropin].

The study made by histochemistry shows that the delta5-3 beta-hydroxysteroid-dehydrogenase (delta5-3 beta-HSDH) activity which is positive in the fresh placental tissue disappears after 24 h of culture but is maintained much longer if culture medium is supplemented with human chorionic gonadotropin (15 UI of HCG). The biochemical study confirms the delta5-3 beta-HSDH activity decrease during the first 24 h of culture. The enzymatic activity is restored during the following six days and this phenomenon is stimulated by the addition of HCG in the culture medium.