title: Effect of food restriction on the metabolism of dimethylnitrosamine (NDMA) in rats.
abstract: The influence of food restriction on the macromolecular interactions of the hepatocarcinogen dimethylnitrosamine (NDMA) in the livers of male Sprague Dawley rats was investigated. Two-three month old rats were food restricted (FR) (40% with respect to ad libitum fed rats) for three weeks. The liver weight, total protein, microsomal and cytoplasmic protein, cytochrome P-450 and DNA content per whole liver were all reduced significantly in food restricted rats. Five hours after a single dose of (14C) NDMA (28 mg/k.b.w., 21 microCi/rat) the levels of 7-methylguanine increased in restricted rats by 32%. Cytochrome P-450 mediated generation of HCHO from NDMA (1.8 fold) in restricted rats was greater. Binding of NDMA derived radioactivity to total hepatic proteins decreased by 46% in restricted rats. These results suggest that food restriction enhances the metabolic activation of dimethylnitrosamine in Sprague Dawley rats.
authors.affiliation: Fels Research Institute, Temple University School of Medicine, Philadelphia, PA 19140.
authors.forename: H R
authors.initials: HR
authors.lastname: Prasanna
authors.forename: R W
authors.initials: RW
authors.lastname: Hart
authors.forename: P N
authors.initials: PN
authors.lastname: Magee
mesh_terms: D000818:Animals; D001711:Biotransformation; D004247:DNA / Q000378:metabolism; D004038:Diet, Reducing; D004128:Dimethylnitrosamine / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D008745:Methylation; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004247:DNA; D004128:Dimethylnitrosamine