The role of glutathione S-transferases in the hepatic metabolism of benzo[a]pyrene in white suckers (Catostomus commersoni) from polluted and reference sites in the Great Lakes.
1. Orally administered 3H-benzo[a]pyrene (3H-BaP) was excreted in the bile of White Suckers predominantly as water soluble metabolites some of which were hydrolyzed by arylsulfatase or beta-glucuronidase. 2. Non-hydrolysible polar metabolites comprised a substantial proportion of biliary metabolites. 3. HPLC analysis revealed fluorescent and 3H-labelled peaks which co-eluted with standards of the glucuronide and sulfate conjugates of BaP. 4. The most polar peak co-chromatographed with a double-radiolabelled metabolite produced in vitro with 3H-BaP and 35S-glutathione. 5. Inhibition of epoxide hydrolase in vitro reduced all water soluble metabolites except the glutathione conjugate of BaP. 6. Glutathione conjugation represents a major hepatic detoxication pathway of BaP in White Suckers.
Kirby
G M
GM
Department of Pathology, University of Guelph, Ontario, Canada.
Bend
J R
JR
Smith
I R
IR
Hayes
M A
MA
D000818:Animals; D001564:Benzo(a)pyrene / Q000493:pharmacokinetics*; D001646:Bile / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003531:Cypriniformes / Q000378:metabolism* / Q000502:physiology; D005982:Glutathione Transferase / Q000302:isolation & purification / Q000502:physiology*; D006114:Great Lakes Region; D006868:Hydrolysis; D008658:Inactivation, Metabolic; D008099:Liver / Q000378:metabolism*; D008297:Male; D012015:Reference Standards; D012016:Reference Values; D014873:Water Pollutants / Q000493:pharmacokinetics*; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics*
D014873:Water Pollutants; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene; D005982:Glutathione Transferase