Modification of nucleic acids with muta-carcinogenic heteroaromatic amines in vivo. Identification of modified bases in DNA extracted from rats injected with 3-amino-1-methyl-5H-pyrido[4,3-b]indole and 2-amino-6-methyldipyrido[1,2-a3:3',2'-d]imidazole.

Potent muta-carcinogens isolated from amino-acid pyrolysates, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and 2-amino-1-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), were injected intraperitoneally into Male Wistar rats. DNA and rRNA modified with these muta-carcinogens were then extracted from the livers of the rats, and modified nucleic-acid bases were isolated and analysed by high-performance liquid chromatography (HPLC). These modified nucleic-acid bases were identified as 3-(C8-guanyl)amino-1-methyl-5H-pyrido[4,3-b]indole (Gua-Trp-P-2) and 2-(C8-guanyl)amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Gua-Glu-P-1) by comparison of their retention times on HPLC and UV spectra with those of authentic compounds.