Mutagenicity of heterocyclic amines when activated by pancreas tissue

The heterocyclic amines (HA) 2-aminodipyridol[1,2-a:3′2-d]imidazole (Glu-P-2), 2-amino-3,4-dimethylimidazo- [4,5-f]quinoline (MeIQ) and 2-amino-l-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were mutagenic in V79 cells (Chinese hamster lung fibrobalsts) using 6-thioguanine resistance as the marker of mutagenicity. Pancreas duct epithelial cells (DEC) from untreated hamsters, homogenates of pancreas ducts from untreated hamsters and those fed a high fat diet and human DEC were used to activate the heterocyclic amines. When hamster cells and tissues were used the optimum mutation frequencies ( mutants/10⁶ survivors) measured were: Glu-P-2, 10±1; MeIQ, 28±2 (DEC), 12±2 (control, duct homogenate, 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]dole and 3-amino-1-methyl-5H-pyridol[4,3-b]indole were not mutagenic in this assay