Differentiation and regulation of peripheral androgen metabolism in rats and rhesus monkeys

The sex-unique metabolic network for steroids is induced neonatally in male rats. The metabolic clearance rates (MCR) of dehydroepiandrosterone and testosterone are similar for both sexes of rats despite quantitatively significant sex differences in individual enzyme activities of adults; neonatally androgenized females had a 2-to 3-fold increase in MCR but cyproterone had no effect. The MCRT and MCRDHA of castrated adult male rhesus monkeys are the same as those of normal males; the MCRDHA is 4-fold greater. Testosterone treatment suppressed the MCRDHA of the castrated groups but estradiol treatment did not. The sex-steroid binding protein (SBP) levels were lower in males than females, and these values were reduced by testosterone. Estrogen suppressed the higher SBP values of females. The sex-steroid milieu of adult rhesus monkeys regulates SBP binding capacity and the enzyme activities of skin measured in vitro. Prenatal testosterone does not exert a crucial role in presetting the peripheral metabolic network in rhesus monkeys.