title: A study of the metabolism of methamphetamine and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in isolated rat hepatocytes.
abstract: The metabolism of methamphetamine (MA) and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in freshly isolated rat hepatocytes was investigated, and compared with in vivo results. A suspended hepatocyte culture, established from male Wistar rats using a collagenase perfusion technique, was incubated in the presence of MA or 2C-B. After enzymatic hydrolysis of the conjugated forms, the metabolites were extracted by liquid-liquid partition and analyzed by gas chromatography/mass spectrometry (GC/MS). Amphetamine, p-hydroxymethamphetamine and p-hydroxyamphetamine were detected in the culture fluids of the rat hepatocytes inoculated with MA. The alcohol derivative, carboxylic acid derivative, 2-O-desmethyl-2C-B, 2-O-desmethyl-N-acetyl-2C-B and 5-O-desmethyl-N-acetyl-2C-B were detected in the case of 2C-B. The major metabolite of MA in rat hepatocytes was p-hydroxymethamphetamine. This is in good agreement with the urinary excretion profile for rats that were fed MA. 2-O-Desmethyl-2C-B and the carboxylic acid derivative were the major recovered metabolites of 2C-B in the rat hepatocyte culture, a slight deviation from the in vivo findings, in which 5-O-desmethyl-N-acetyl-2C-B was found to be the main component. Metabolites with a hydroxy group were largely present in their conjugated forms in the culture fluids, except for 2-O-desmethyl-2C-B. Taking these results into consideration, a primary hepatocyte culture system has the potential to provide a quick and handy method for estimating the in vivo metabolic fate of abused drugs.
authors.affiliation: National Research Institute of Police Science, 6-3-1, Kashiwanoha, Kashiwa-shi, Chiba 277-0882, Japan. kanamori@nrips.go.jp
authors.forename: T
authors.initials: T
authors.lastname: Kanamori
authors.forename: K
authors.initials: K
authors.lastname: Tsujikawa
authors.forename: Y
authors.initials: Y
authors.lastname: Ohmae
authors.forename: Y T
authors.initials: YT
authors.lastname: Iwata
authors.forename: H
authors.initials: H
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Kishi
authors.forename: T
authors.initials: T
authors.lastname: Nakahama
authors.forename: Y
authors.initials: Y
authors.lastname: Inouye
mesh_terms: D004290:DOM 2,5-Dimethoxy-4-Methylamphetamine / Q000031:analogs & derivatives* / Q000378:metabolism*; D000661:Amphetamine / Q000378:metabolism; D000818:Animals; D002264:Carboxylic Acids / Q000737:chemistry; D002478:Cells, Cultured; D000697:Central Nervous System Stimulants / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D006213:Hallucinogens / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism*; D008297:Male; D008694:Methamphetamine / Q000031:analogs & derivatives* / Q000378:metabolism*; D023421:Models, Animal; D015394:Molecular Structure; D051381:Rats; D017208:Rats, Wistar; D013566:Sympathomimetics / Q000378:metabolism; D010136:p-Hydroxyamphetamine / Q000378:metabolism
chemical_list: C500181:2-O-desmethyl-4-bromo-2,5-dimethoxyphenethylamine; C500180:2-O-desmethyl-N-acetyl-4-bromo-2,5-dimethoxyphenethylamine; D002264:Carboxylic Acids; D000697:Central Nervous System Stimulants; D006213:Hallucinogens; D013566:Sympathomimetics; D004290:DOM 2,5-Dimethoxy-4-Methylamphetamine; C003943:2,5-dimethoxy-4-bromoamphetamine; D008694:Methamphetamine; C005877:pholedrine; D000661:Amphetamine; D010136:p-Hydroxyamphetamine