Effects of 6-aminochrysene on liver microsomal enzyme activity.

1. No transformation of 6-aminochrysene took place during its incubation with rat liver microsomes under oxygen or anaerobic conditions. 2. 6-Aminochrysene inhibited the hydroxylation of aniline, O-demethylation of p-nitroanisole, and N-demethylation of aminopyrine by rat liver microsomes. 3. Pre-treatment of rats with 6-aminochrysene markedly decreased the N-demethylation in vitro but significantly increased the hydroxylation and the O-demethylation. Similar effects were observed also with microsomal preparations from livers perfused with 6-aminochrysene.