Formation of DNA-binding products from isolated benzo[a]pyrene metabolites in rat liver nuclei.
Liver nuclei from 3-methylcholanthrene-treated rats in the presence of NADPH metabolized 3- and 9-hydroxybenzo[a]pyrene and 7,8-dihydro-7,8-dihydroxybenzo[a]pyrene to products that bound to DNA. Maximal binding was obtained with the dihydrodiol which was approximately 3-fold that with 9-hydroxybenzo[a]pyrene, and 60-fold that with 3-hydroxybenzo[a]pyrene, as substrates. Both 4,5-dihydro-4,5-dihydroxybenzo[a]pyrene and 9,10-dihydro-9,10-dihydroxybenzo[a]pyrene were also extensively metabolized by the nuclear fraction but did not give rise to DNA-binding products. The available evidence suggests that the DNA binding species derived from 9-hydroxy-benzo[a]pyrene is 9-hydroxy-benzo[a]pyrene-4,5-oxide and from 7,8-dihydro-7,8-dihydroxybenzo[a]pyrene, as previously observed in different systems, 7,8-dihydro-7,8-dihydroxy-benzo[a]pyrene-9,10-oxide.
D000818:Animals; D001580:Benzopyrenes / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats
D001580:Benzopyrenes; D004247:DNA