title: Distribution and excretion of 2,2',3,4',5,5',6-heptachlorobiphenyl (CB187) and its metabolites in rats and guinea pigs.
abstract: 4-Hydroxy (OH)-2,2',3,4',5,5',6-heptachlorobiphenyl (CB187) is a polychlorinated biphenyl (PCB) metabolite present in human serum at the highest concentration of the PCB metabolites. Our previous study demonstrated that CB187 was metabolized by rat and guinea pig liver microsomes to the major metabolite 4'-OH-2,2',3,3',5,5',6-heptachlorobiphenyl (CB178), and the two minor metabolites 4-OH-CB187 and 4'-OH-2,2',3,5,5',6-hexachlorobiphenyl (CB151). In this study, the distribution of these metabolites in serum, liver and kidney, and their fecal excretion, were examined in rats and guinea pigs intraperitoneally dosed with CB187. Similarly to the in vitro study, 4'-OH-CB178 was a major metabolite in the liver, serum and feces of both animal species on day 4 after CB187 injection, and the level in the liver was about 20 times higher in untreated guinea pigs than in untreated rats. In addition, 4-OH-CB187, a minor metabolite, was detected in the serum and kidneys, but not in the feces, of both guinea pigs and rats. Another minor metabolite, 4'-OH-CB151, was detected at a lower level only in guinea pig feces; little was found in the serum or liver of either animals. Over the 30d following CB187 injection into guinea pigs, 4'-OH-CB178 and 4-OH-CB187 in the serum was observed at higher level on day 4 and day 16 after injection, respectively. The majority of the 4'-OH-CB178 was rapidly excreted to the feces following unmetabolized CB187, whereas 4-OH-CB187 was not found in guinea pig feces and liver during 30d. These results support previous reports that 4-OH-CB187 is retained persistently in animal blood.
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, 5-7-1 Befu, Jonan-ku, Fukuoka 814-0198, Japan. Electronic address: chiho@nakamura-u.ac.jp.
authors.forename: Chiho
authors.initials: C
authors.lastname: Ohta
authors.affiliation: Daiichi College of Pharmaceutical Sciences, 22-1 Tamagawa-cho, Minami-ku, Fukuoka 815-8511, Japan. Electronic address: k-haraguti@daiichi-cps.ac.jp.
authors.forename: Koichi
authors.initials: K
authors.lastname: Haraguchi
authors.affiliation: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan. Electronic address: kato@kph.bunri-u.ac.jp.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293, Japan. Electronic address: endotty@hoku-iryo-u.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Endo
authors.affiliation: Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293, Japan. Electronic address: o_kimura@hoku-iryo-u.ac.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Kimura
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, 5-7-1 Befu, Jonan-ku, Fukuoka 814-0198, Japan. Electronic address: nobuyuki@nakamura-u.ac.jp.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Koga
mesh_terms: D000818:Animals; D004785:Environmental Pollutants / Q000097:blood / Q000378:metabolism*; D005243:Feces / Q000737:chemistry; D006168:Guinea Pigs; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D011078:Polychlorinated Biphenyls / Q000097:blood / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004785:Environmental Pollutants; C000598729:2,2',3,4',5,5',6-heptachlorobiphenyl; D011078:Polychlorinated Biphenyls
keywords: CB187; Distribution; Feces; Liver; Metabolism; Serum