Effects of Phenothiazines on Protective Systems against Polycyclic Hydrocarbons.

A study was initiated to find compounds which have the capacity to induce high levels of activity of microsomal systems detoxifying polycycic hydrocarbons. Of a large number of chemicals and dietary constituents, only phenothiazine and several of its derivatives were found to be potent inducers of an increased benzpyrene hydroyxlase activity. These phenothiazines also protected rats against adrenal necrosis following a massive oral dose of 7 , 12-dimethylbenz(a)anthracene (DMBA). Related hetero cyclic compounds in which the nitrogen or sulfur atoms of the phenothiazine ring are replaced had considerably weaker or no inducing capacity.