Metabolism of [14C]-C21 steroids in the human fetal ovaries.

The incubation of [14C]-pregnenolone with the mince of human fetal ovary produced progesterone. 17-hydroxypregnenolone, 5-pregnene-3 beta, 20 alpha-diol. 5-pregnene-3 beta, 17 alpha, 20 alpha-triol and 5 alpha-pregnan-3,20-dione. The other 7 tissues, uterus, liver, intestine, skin, kidney, lung and pancreas, obtained from the same fetus were also able to produce some of these metabolites. When [14C]-pregnenolone, progesterone or 17-hydroxyprogesterone was incubated with 800 g supernatant of fetal ovaries, progesterone, 17-hydroxypregnenolone and 5-pregnene-3 beta, 20 alpha-diol were formed from pregnenolone, 17-hydroxyprogesterone and 20 alpha-hydroxy-4-pregnen-3-one were formed from progesterone and 17 alpha, 20 alpha-dihydroxy-4-pregnen-3-one was formed from 17-hydroxyprogesterone. These results indicate that the fetal ovary has the activities of 5-ene-3 beta-hydroxysteroid dehydrogenase, 17-hydroxylase, 20 alpha-hydroxysteroid dehydrogenase and 5 alpha-reductase.