title: [Metabolism of 2,3,3',4,4'-pentachlorobiphenyl in hamsters].
abstract: The in vivo metabolism of 2,3,3',4,4'-pentachlorobiphenyl (CB105) was studied in hamsters and the effect of cytochrome P450 inducers, phenobarbital (PB) and 3-methylcholanthrene (MC) on its metabolism was compared to rats. After administration of CB105 intraperitoneally at a dose of 3 mg/body, four metabolites, named M-1, M-2, M-3 and M-4, were detected in 5 days-feces of all groups and the formation ratio of the metabolites M-1-M-4 was 1:39:84:0.2 in untreated hamsters and 1:19:6.7:0.7 in untreated rats. On the basis of the mass spectra of four synthetic authentic compounds and the retention times on DB-1 and MPS50 columns, M-1, M-2, M-3 and M-4 were identified as 4'-hydroxy-2,3,3',4,5'-PenCB, 5'-hydroxy-CB105, 5-hydroxy-CB105 and 4-hydroxy-2,3,3',4',5-PenCB, respectively. The pretreatment of PB and MC resulted in about 2-fold fecal excretion of four metabolites in hamsters and in about 3-fold in rats. Of four metabolites, only M-4 were detected in the serum at 5 days after CB105 administration and the concentration was 0.39 microgram/ml of hamster serum and 0.28 microgram/ml of rat serum. In hamsters, the concentration of M-4 was increased to 1.8-fold of untreated animals by PB treatment and 2.6-fold by MC treatment. On the other hand, the treatment of rats with PB and MC did not show such an increase of serum M-4. These results suggested that the hamster oxidized 2,3,4-trichloro-substituted benzene ring predominantly rather than 3',4'-dichloro-substituted benzene ring differently from the rat and that M-4 formed in hamster liver distributed to the blood and retained there to a considerable extent in comparison with that formed in rat liver.
authors.affiliation: Department of Nutritional Sciences, Nakamura Gakuen University, 5-7-1, Befu, Johnan-ku, Fukuoka 814-0198.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Koga
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kuroki
authors.forename: Koichi
authors.initials: K
authors.lastname: Haraguchi
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Kanamaru
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kato
authors.forename: Ryohei
authors.initials: R
authors.lastname: Kimura
mesh_terms: D000818:Animals; D006224:Cricetinae; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis; D004790:Enzyme Induction / Q000187:drug effects; D008297:Male; D008647:Mesocricetus; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013045:Species Specificity; D013329:Structure-Activity Relationship
chemical_list: D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D011078:Polychlorinated Biphenyls; D010634:Phenobarbital