Metabolism of 3,3',4,4'-tetrachlorobiphenyl via sulphur-containing pathway in rat: liver-specific retention of methylsulphonyl metabolite.
1. Single doses of 3,3',4,4'-tetrachlorobiphenyl (TCB) were administered intraperitoneally to the male Wistar rat for metabolism studies. 2. Seven sulphur-containing metabolites of TCB were isolated from faeces, in addition to previously reported 4-hydroxy-3,3',4',5-tetrachlorobiphenyl and 5-hydroxy-TCB. Major sulphur-containing metabolites were 5- and 6-methylthio-TCBs, and 6-methylsulphonyl-3-methylthio-3',4,4'-trichlorobiphenyl. 3. The faecal excretions of hydroxy metabolites, methylthio metabolites and unchanged TCB accounted for 7.1, 0.5 and 0.3% of the dose respectively within 4 days after administration. 4. 5-Methylsulphonyl-TCB was detected and selectively retained in liver. The concentration ratio of 5-methylsulphonyl-TCB and unchanged TCB in liver was 1:4. 5. Following administration of 5- and 6-methylsulphonyl-TCBs to rat, 5-methylsulphonyl-TCB was localized in liver, whereas 6-methylsulphonyl-TCB was rapidly biotransformed to 6-methylsulphonyl-3-methylthio-3',4,4'-trichlorobiphenyl and excreted in the faeces.
Haraguchi
K
K
Daiichi College of Pharmaceutical Sciences, Fukuoka, Japan.
Kato
Y
Y
Masuda
Y
Y
Kimura
R
R
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001711:Biotransformation; D005243:Feces / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D011078:Polychlorinated Biphenyls / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
D011078:Polychlorinated Biphenyls; C028451:3,4,3',4'-tetrachlorobiphenyl