title: Immunoquantitation of cytochromes P450 1A and P450 2B and comparison with chlorinated hydrocarbon levels in archived polar bear liver samples.
abstract: The present study examined the utility of an immunoblot method for quantitation of cytochrome P450 isozymes in archived liver samples as a bioassay of exposure to halogenated hydrocarbons. Hepatic microsomes were prepared from 44 archived polar bear (Ursus maritimus) liver homogenates that had been stored at approximately -40 degrees C for 9-10 years and analyzed on blots probed with antibodies to rat cytochromes P450 1A1 and P450 2B1. The results revealed a positive correlation between cytochrome P450 1A and total polychlorinated biphenyl (PCB) levels in the archived liver samples, suggesting that cytochrome P450 1A was induced in polar bears by environmental exposure to PCBs.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, Canada.
authors.forename: S M
authors.initials: SM
authors.lastname: Bandiera
authors.forename: S M
authors.initials: SM
authors.lastname: Torok
authors.forename: R J
authors.initials: RJ
authors.lastname: Letcher
authors.forename: R J
authors.initials: RJ
authors.lastname: Norstrom
mesh_terms: D000818:Animals; D001681:Biological Assay; D015925:Cryopreservation; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis*; D019362:Cytochrome P-450 CYP2B1 / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D015151:Immunoblotting; D016014:Linear Models; D008099:Liver / Q000737:chemistry* / Q000201:enzymology; D008297:Male; D001503:Ursidae / Q000378:metabolism*
chemical_list: D006843:Hydrocarbons, Chlorinated; D019363:Cytochrome P-450 CYP1A1; D019362:Cytochrome P-450 CYP2B1