DIFFERENTIAL CARCINOGENICITY OF BENZO[A]PYRENE IN MALE AND FEMALE CD-1 MOUSE LUNG

Benzo[a]pyrene (BaP) is known to induce tumors in lung, forestomach, a nd skin in experimental animals. Earlier studies have suggested that g lutathione S-transferase pi (GST pi) is involved in the detoxification of the ''ultimate'' carcinogenic metabolite of BaP, 7 beta, 8 alpha-d ihydroxy-9 alpha, 10 alpha-oxy-7,8,9, 10-tetrahydrobenzo[a]pyrene (BPD E). The constitutive expression of GST pi in the liver of the male CD- 1 mouse is higher than that of the female, and BHA has been shown to p referentially induce GST pi in the female as compared with the male mo use. The present studies were therefore designed to compare the suscep tibility of male and female CD-1 mice to the carcinogenic effects of B aP and the protective effect of BHA. Results of these studies show tha t the female CD-1 mice are more susceptible to the carcinogenic effect of BaP than the males and that the attenuation of BaP-induced carcino genesis by BHA appears to be restricted only to the females.