title: PCBs and PBBs: biologic and toxic effects on C57BL/6J and DBA/2J inbred mice.
abstract: Treatment of genetically inbred "responsive" C57BL/6J and "non-responsive" DBA/2J mice with Aroclor 1254 or fireMaster BP-6 resulted in the induction of hepatic microsomal benzo[a]pyrene hydroxylase only in the former mouse strain and aminopyrine N-demethylase in both strains of mice. In contrast, 3,3',4,4',5-pentachlorobiphenyl and 3,3',4,4'-tetrabromobiphenyl, induced benzo[a]pyrene hydroxylase in both C57BL/6J and DBA/2J but did not enhance aminopyrine N-demethylase in either strain of mouse. Both these coplanar halogenated biphenyls also caused thymic atrophy in the responsive and non-responsive mice and their effects resembled those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Treatment of the inbred mice with several mono-ortho substituted analogs of the coplanar halogenated biphenyls, including 2,3,3',4,4'-pentachloro-, 2,3',4,4',5-pentabromo-, 2,3,3',4,4',5-hexachloro- and 3',4'-dibromo-2,3,4,5-tetrachlorobiphenyl, gave hepatic enzyme-induction results similar to those observed for the commercial halogenated biphenyls. At dose levels of 1500 mumol/kg, most of these compounds caused thymic atrophy in C57BL/6J mice but not in DBA/2J mice. The structure-activity correlations in the mice complement similar studies with the halogenated biphenyls in rats and support the proposed receptor-mediated mechanism for the toxic halogenated aromatics.
mesh_terms: D000633:Aminopyrine N-Demethylase / Q000096:biosynthesis; D000818:Animals; D001579:Benzopyrene Hydroxylase / Q000096:biosynthesis; D004790:Enzyme Induction / Q000187:drug effects; D008099:Liver / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009929:Organ Size / Q000187:drug effects; D011075:Polybrominated Biphenyls / Q000633:toxicity*; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity; D013045:Species Specificity; D013329:Structure-Activity Relationship
chemical_list: D011075:Polybrominated Biphenyls; D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls; D001579:Benzopyrene Hydroxylase; D000633:Aminopyrine N-Demethylase