Hepatic microsomal enzyme induction by trifluoromethyl compounds and some halogenated and nonhalogenated analogs.

Trifluoromethyl derivatives of toluene, phenothiazine, benzimidazole and DDT were administered ip to male rats for 5 days and induction of hepatic microsomal enzymes catalyzing the metabolism of EPN, p-nitroanisole and aminopyrine measured. The addition of a trifluoromethyl substituent to toluene, phenothiazine and benzimidazole increased the inducing capacity of the parent molecule on p-nitroanisole metabolism. Dihalogenation of benzene with trifluoromethyl groups, regardless of position, resulted in induction of p-nitroanisole metabolism whereas halogenation of benzene with trichloromethyl groups did not. For these compounds, the size and electron-inducing capacity of the halogenated substituent may be relative to microsomal enzyme induction.