Partial masculinization of rat liver enzyme activities following treatment with FSH.

The metabolism of 4-(4014C)androstene-3,17-dione and 5alpha-(4-14C)androstene-3alpha, 17beta-diol was studies in the microsomal fraction and that of 4-(4-14C) androstene-3,17-dione in the 105,000 times g supernatant fraction of livers from castrated male and female rats treated with LH and FSH. Administration of LH led to significant decreases in 17-hydroxysteroid reduction and 7alpha-hydroxylation of 4-androstene-3,17-dione in both male and female rats and in 6beta-hydroxylation of 4-androstene-3,17-dione in female rats. FSH on the other hand specifically stimulated (masculinized) the following sex-dependent hydroxylations: 16alpha-hydroxylation of 4-androstene-3,17-dione in female rats and 2alpha-, and 2beta- and 18-hydroxylation of 5alpha-androstane-3alpha,17beta-diol in male rats. The metabolism of 4-androstene-3,17-dione and 5alpha-androstane-3alpha,17beta-diol was also studied in castrated male and female rats given testosterone propionate and in castrated female rats given testosterone propionate in combination with LH or FSH. It was shown that neither LH nor FSH could compensate for the relative androgen-unresponsiveness exhibited by female as compared to male rats. It is concluded that FSH but not LH may participate in the regulation of sex-dependent hydroxylase systems in rat liver.?2,Author