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-triazine herbicide, was administered to young male rats. There was a significant increase of the in vivo elimination of hexobarbital and a significant induction of the activity of 7-pentoxyresorufin-O-dealkylase, while cytochrome P-450 content and other mixed function oxidase activities remained unaltered. The administration of carbon tetrachloride (CCl4) to atrazine pretreated rats did not substantially augment the impairment of drug metabolizing enzymes brought about by CCl4 alone. Results suggest that atrazine behaves like a relatively weak inducer of phenobarbital-inducible families of cytochrome P-450.