INDUCTION OF CHROMOSOMAL-ABERRATIONS AND 8-AZAGUANINE-RESISTANT MUTATIONS BY ARYLDIALKYLTRIAZENES IN CULTURED MAMMALIAN-CELLS

Inducibility of chromosomal aberrations, cell survival and mutation to 8-azaguanine (8AG) resistance in cultured [Chinese hamster lung] V79 cells by 1-phenyl-3,3-dimethyltriazene (PDMT), 1-phenyl-3,3-diethyltriazene (PDET) and 1-(pyridyl-3)-3,3-diethyltriazene (PyDET) were examined with or without metabolic activation. Chromosomal aberrations were induced in a dose-dependent manner by all 3 triazenes in a direct treatment for 24 h. Chromosomal aberrations were also induced by PDMT with a metabolic activation system for 3 h, and little differences in the incidence were observed compared with those obtained by a direct treatment. All 3 triazenes were slightly mutagenic in a direct treatment for 24 h. In metabolic activation experiments, PDMT and PyDET were highly mutagenic. The mutagenicity, when compared with the cytotoxicity, was significantly higher in a metabolic activation system than in a direct treatment.