G. Lower, G. Bryan
Jul 1, 1973
Citations
1
Influential Citations
88
Citations
Quality indicators
Journal
Biochemical pharmacology
Abstract
Abstract The relative capability of N -acetyltransferase enzyme systems from liver cytosol of various mammalian species to carry out the transfer of acetyl groups from acetyl-CoA to the amine function of the carcinogens, 2-aminofluorene, 4-aminobiphenyl and 2-aminonaphthalene, was investigated. The carcinogenic arylamines were incubated with liver cytosol in the presence of acetyl-1- 14 C-C6A and enzyme activity was estimated by quantitation of the resulting 14 C-labeled arylacetamides. In hamsters, guinea pigs, mice and rats, 2-aminofluorene was the superior substrate followed in order by 4-aminobiphenyl and 2-aminonaphthalene. Highest enzyme activity was present in liver cytosol from the hamster, followed in order by hepatic cytosol from the guinea pig, mouse and rat. In contrast, dog liver cytosol was incapable of carrying out detectable N -acetylation of any of the three carcinogenic arylamines studied. Administration of a variety of carcinogenic arylamines to dogs has resulted in the formation of only urinary bladder tumors, the liver apparently being refractory to this type of carcinogenic insult. In contrast, administration of carcinogenic arylacetamides to dogs has resulted in the unequivocal formation of both urinary bladder tumors and hepatomas. These considerations suggest that N -acetylation is not required for carcinogenesis of the urinary bladder and that the expression of urinary bladder or hepatocarcinogenicity by arylamines and arylacetamides in a given experimental system may depend on the quantitative ability of the species being studied to utilize pathways for the interconversion of arylacetamide derivatives and arylamine derivatives.