Effects of chlorinated diphenyl ethers on the mixed-function oxidases and ultrastructure of rat and trout liver.
The effects of chlorinated diphenyl ethers (CDEs) on hepatic mixed-function oxidase (MFO) activities and ultrastructure were examined in the rat and trout after ip administration of 100 mg/kg/day of 4-chlorodiphenyl ether (4-CDE), 2,4-dichlorodiphenyl ether (2,4-diCDE), 2,4,4'-trichlorodiphenyl ether (2,4,4'-triCDE), or 2,4,5,4'-tetrachlorodiphenyl ether (2,4,5,4'-tetraCDE) for 3 days. The 4-CDE, 2,4-diCDE, and 2,4,4'-triCDE pretreatments did not alter significantly the MFO activities of trout liver; however, 2,4,5,4'-tetraCDE pretreatment increased significantly the hepatic cytochrome b5 content and 7-ethoxycoumarin O-deethylase activity of trout liver. No histological changes were observed in the hepatocytes of trout treated with any of the CDEs. Pretreatment of rats with 4-CDE and 2,4-diCDE also did not alter significantly the MFO activities of the liver. In contrast, pretreatment of rats with 2,4,4'-triCDE and 2,4,5,4'-tetraCDE increased significantly hepatic MFO activities and also caused a proliferation of smooth endoplasmic reticulum in the liver. 2,4,4'-triCDE and 2,4,5,4'-tetraCDE appear to be a phenobarbital-type inducer and a mixed-type inducer of rat liver MFO activity, respectively.
D015660:7-Alkoxycoumarin O-Dealkylase; D000633:Aminopyrine N-Demethylase / Q000378:metabolism; D000818:Animals; D001579:Benzopyrene Hydroxylase / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D003573:Cytochrome b Group / Q000096:biosynthesis; D015786:Cytochromes b5; D004790:Enzyme Induction; D004987:Ethers; D005260:Female; D007274:Injections, Intraperitoneal; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008297:Male; D006899:Mixed Function Oxygenases / Q000096:biosynthesis*; D009929:Organ Size / Q000187:drug effects; D010105:Oxygenases / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014337:Trout
D003573:Cytochrome b Group; D004987:Ethers; D015786:Cytochromes b5; D011078:Polychlorinated Biphenyls; D006899:Mixed Function Oxygenases; D010105:Oxygenases; D015660:7-Alkoxycoumarin O-Dealkylase; D001579:Benzopyrene Hydroxylase; D000633:Aminopyrine N-Demethylase