[The thioacetamide-poisoned rat as an animal experimental model for endocrinological studies of estrogen metabolism in chronic liver injury)].

Liver microsomes of rats poisoned with thioacetamide show a significant reduction of cytochrome P-450. Consequently, oxidative reactions of drug metabolism and the estrogen 2-hydroxylase are diminished. Enhancement of microsomal transformation of estradiol to estrone and 16alpha-hydroxyestrone is observed after treatment of rats with thioacetamide, due to diminished metabolism of estradiol by the alternative oxidation at C-2. Estriol formation is reduced by thioacetamide pretreatment. These changes in estrogen breakdown closely correlate with those observed in humans suffering from cirrhosis of the liver. It is concluded that the thioacetamide poisoned rat should be an experimental model suitable for studying estrogen metabolism in liver injury.