MUTAGENICITY OF HETEROCYCLIC AMINES WHEN ACTIVATED BY PANCREAS TISSUE

The heterocyclic amines (HA) 2-aminodipyrido[1,2-a:3',2-d]imidazole (G lu-P-2), 2-amino-3,4-dimethylimidazo-[4,5-f]quinoline (MeIQ) and 2-ami no-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were mutagenic in V7 9 cells (Chinese hamster lung fibroblasts) using 6-thioguanine resista nce as the marker of mutagenicity. Pancreas duct epithelial cells (DEC ) from untreated hamsters, homogenates of pancreas ducts from untreate d hamsters and those fed a high fat diet and human DEC were used to ac tivate the heterocyclic amines. When hamster cells and tissues were us ed the optimum mutation frequencies (mutants/10(6) survivors) measured were: Glu-P-2, 10+/-1; MeIQ, 28+/-2 (DEC), 12+/-2 (control, duct homo genate), and 21+/-2 (high fat diet fed, duct homogenate); PhIP, 61+/-5 . When human DEC were used the optimum mutation frequencies were: MeIQ , 32+/-4; PhIP, 35+/-3.3,8-dimethylimidazo[4,5-f]quinoxaline, 3-amino- 1,4-dimethyl-5H-pyrido[4,3-b]indole and 3-amino-1-methyl-5H-pyrido[4,3 -b]indole were not mutagenic in this assay.