Binding of metabolically activated benzo(a)pyrene to DNA and histones of rat liver,lung and regenerating liver

Binding of metabolically activated benzo(a)pyrene (BP) to the DNA and histones of nuclei isolated from rat liver, lung, and regenerating liver was examined. Separation of enzymically degraded DNA by Sephadex LH-20 chromatography resulted in several peaks of radioactivity and the major peak was probably derived from the binding of 7,8-diol-9,10-epoxide of BP with DNA. A high level of BP metabolites was also bound to the Hl histone fraction. The patterns of BP binding with the components of nuclei from the different cell types were similar. Implications of these observations as related to carcinogenic tissue susceptibility are discussed.