Species differences in the tissue distribution of catechol and methylsulphonyl metabolites of 2,4,5,2',5'-penta- and 2,3,4,2',3',6'-hexachlorobiphenyls in rats, mice, hamsters and guinea pigs.
Polychlorinated biphenyls (PCBs) are metabolized to phenolic or methylsulphonyl PCBs (MeSO(2)-CBs) in animal species. The study determined the species differences in the tissue distribution of persistent PCB metabolites in rats, mice, hamsters and guinea pigs 4 days after exposure to 2,4,5,2('),5(')-pentachlorobiphenyl (CB101) or 2,3,4,2('),3('),6(')-hexachlorobiphenyl (CB132). For CB101 metabolism, the hydroxylation in rats, mice and hamsters occurred primarily at the 3(')-position in the 2('),5(')-dichlorinated phenyl ring, whereas the hydroxylation in guinea pigs occurred preferentially at the 3-position. Metabolite profiles in tissues of hamsters were dominated by 3('),4(')-catechol-CB101, whereas metabolite profiles in rats and mice were dominated by 3(')- or 4(')-MeSO(2)-CBs. For CB132 metabolism, rats and mice produced 4(')- and 5(')-MeSO(2)-CBs at similar concentration ratios, whereas guinea pigs produced MeSO(2)-CBs at higher levels and selectively retained 5(')-MeSO(2)-CB in liver. In contrast, hamsters preferentially produced 4('),5(')-catechol-CB132 that was retained in serum. Consequently, hamsters produced catechols, whereas guinea pigs produced meta-substituted MeSO(2)-CBs, preferentially from CB132. These findings indicate that PCBs with 2,3,6-chlorine substitution are preferred substrates for the formation of catechols or MeSO(2)-CBs and the differences in metabolite profiles are related to species-dependent metabolic capacities.
Haraguchi
K
K
Daiichi College of Pharmaceutical Sciences, Fukuoka, Japan. ko-ichi@ka2.so-net.ne.jp
Kato
Y
Y
Koga
N
N
Degawa
M
M
D000818:Animals; D006224:Cricetinae; D006168:Guinea Pigs; D008099:Liver / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D051379:Mice; D008815:Mice, Inbred Strains; D009928:Organ Specificity; D011078:Polychlorinated Biphenyls / Q000097:blood* / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D013045:Species Specificity
C029790:2,2',3',4,4',5-hexachlorobiphenyl; C009828:2,4,5,2',5'-pentachlorobiphenyl; D011078:Polychlorinated Biphenyls