INDUCTION OF HEPATIC DRUG-METABOLIZING-ENZYMES AND INTERACTION WITH CARBON-TETRACHLORIDE IN RATS AFTER A SINGLE ORAL-EXPOSURE TO ATRAZINE

A single oral dose (430 mg/kg) of atrazine, a widely employed s-triazi ne herbicide, was administered to young male rats. There was a signifi cant increase of the in vivo elimination of hexobarbital and a signifi cant induction of the activity of 7-pentoxyresorufin-O-dealkylase, whi le cytochrome P-450 content and other mixed function oxidase activitie s remained unaltered. The administration of carbon tetrachloride (CCl4 ) to atrazine pretreated rats did not substantially augment the impair ment of drug metabolizing enzymes brought about by CCl4 alone. Results suggest that atrazine behaves like a relatively weak inducer of pheno barbital-inducible families of cytochrome P-450.