title: Comparative gastrointestinal enzyme activity and activation of the promutagen 2,6-dinitrotoluene in male CD-1 mice and male Fischer 344 rats.
abstract: Comparative intestinal nitroreductase, azo reductase, beta-glucuronidase, dechlorinase and dehydrochlorinase activities in young male Fischer 344 rats and young male CD-1 mice were measured in vitro while the comparative biotransformation of 2,6-dinitrotoluene to mutagenic metabolites was determined in vivo. The mice, which exhibit a high spontaneous incidence of hepatomas, had markedly greater nitroreductase activity and metabolized significantly more 2,6-dinitrotoluene to mutagenic metabolites than did Fischer 344 rats, which show a low incidence of liver tumors. Results of this study indicate that species differences in the incidence of hepatomas may be influenced by microbial flora and/or the biotransformation of xenobiotics in the G.I. tract.
authors.affiliation: Health Effects Research Laboratory Environmental Research Center, U.S. Environmental Protection Agency Research, Triangle Park, N.C. 27711.
authors.forename: R W
authors.initials: RW
authors.lastname: Chadwick
authors.forename: S E
authors.initials: SE
authors.lastname: George
authors.forename: J
authors.initials: J
authors.lastname: Chang
authors.forename: M J
authors.initials: MJ
authors.lastname: Kohan
authors.forename: J P
authors.initials: JP
authors.lastname: Dekker
authors.forename: J E
authors.initials: JE
authors.lastname: Long
authors.forename: M C
authors.initials: MC
authors.lastname: Duffy
mesh_terms: D000818:Animals; D001711:Biotransformation; D004136:Dinitrobenzenes / Q000378:metabolism*; D005966:Glucuronidase / Q000378:metabolism; D007422:Intestines / Q000201:enzymology*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced; D008190:Lyases / Q000378:metabolism; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009578:Nitrobenzenes / Q000378:metabolism*; D009601:Nitroreductases / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D004136:Dinitrobenzenes; D009578:Nitrobenzenes; D009601:Nitroreductases; D005966:Glucuronidase; D008190:Lyases; C023514:2,6-dinitrotoluene