title: Influence of prior dietary protein intake on metabolism, DNA binding and adduct formation of 7,12-dimethylbenz[a]anthracene in isolated rat mammary epithelial cells.
abstract: These studies were designed to examine the influence of prior dietary protein intakes in rats on the ability of their isolated mammary cells to metabolize 7,12-dimethylbenz[a]anthracene (DMBA). Total metabolism of DMBA increased as dietary protein increased. After 6 h of incubation, water-soluble metabolites made only a minor (less than 12%) contribution to total DMBA metabolism. The binding of DMBA to isolated mammary cell DNA after 6 h of incubation from rats fed 15% dietary protein was 20% higher than binding from cells of rats fed 7.5% dietary protein. The increased binding in mammary epithelial cells from rats fed 15% protein was associated with an increase in the syn-dihydrodiol-epoxide adduct. The syn-dihydrodiol-epoxide:deoxyadenosine adduct was the major contributor to binding. The present studies are consistent with a decrease in carcinogen activation in tissues obtained from animals fed diets limiting in protein.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D001711:Biotransformation; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000378:metabolism*; D003839:Deoxyadenosines / Q000378:metabolism; D003849:Deoxyguanosine / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D005260:Female; D008321:Mammary Glands, Animal / Q000378:metabolism*; D051381:Rats
chemical_list: D003839:Deoxyadenosines; D004044:Dietary Proteins; D015127:9,10-Dimethyl-1,2-benzanthracene; D004247:DNA; D003849:Deoxyguanosine