The in vitro metabolism of progesterone, 4-androstene-3,17-dione, testosterone and 17β-hydroxy-5α-androstan-3-one by fetal rhesus monkey testes

Homogenates prepared from fetal rhesus monkey testes were incubated with progesterone, 4-androstene-3,17-dione, testosterone and 17β-hydroxy-5α- androstan-3-one. The major progesterone metabolite was 17-hydroxy-4-pregnene-,20-,20-dione. Testosterone also accumulated in the progesterone incubations. 4-Androstene-3,17-dione was converted chiefly to testosterone. Testosterone was not actively metabolized by the fetal monkey testis. 17β-Hydroxy-5α-androstan-3-one was actively converted primarily to 5α-androstane-3β,17β-diol.