Metabolism of 2,2',3,4',5,5'-hexachlorobiphenyl (cb146) by Liver Microsomes from Rats, Hamsters and Guinea Pigs
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چکیده
Introduction Some hydroxy (OH)-metabolites of various PCB congeners such as 4-OH-2,2',3,4',5,5',6-heptachlorobiphenyl (CB187), 4-OH-2,2',3,4',5,5'-hexachlorobiphenyl (hexaCB) (CB146), 4-OH-2,3,3',4',5-pentachlorobiphenyl (CB107), 3'-OH-2,2',3,4,4',5'-hexaCB (CB138) and 3-OH-2,2',4,4',5,5'-hexaCB (CB153) have been found in human blood at higher concentrations. Recent studies have shown that such OH-metabolites possess various toxicological activities to disturb homeostasis of thyroid hormone and vitamin A in animal blood, to behave as an estrogen or antiestrogen and to inhibit estrogen sulfotransferase. However, which PCB congener is the mother compound of the OH-metabolites remains obscure. These OH-metabolites is thought to be formed via a direct hydroxylation or via an epoxide formation and subsequent NIH-shift of chlorine. Recently, we have demonstrated that 4-OH-CB187 could be produced from CB187 but not from 2,2',3,4,4',5',6-heptachlorobiphenyl (CB183) in rats and guinea pigs. 10
منابع مشابه
KINETIC, ENZYME INDUCTION, AH-RECEPTOR In vitro metabolism of 2,2',3,4',5,5',6- heptachlorobiphenyl(CB187) with liver microsomes of rats, hamsters and guinea pigs
ORGANOHALOGEN COMPOUNDS – Volume 66 (2004) 2882 Introduction PCB congeners possess extremely high lipophilicity and biological stability, and as a result they are not easily eliminated from the body once ingested. In particular, not only 2,4,5-trichlorosubstituted but also 6 or more chlorine-substituted PCBs such as 2,2’,3’,4,4’,5-hexa-chlorobiphenyl (hexaCB) (CB138), 2,2’,4,4’,5,5’-hexaCB (CB1...
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