[DNA reparative synthesis in liver cell cultures from mice with various susceptibilities to spontaneous hepatic carcinogenesis].

Ultra-violet radiation-induced unscheduled DNA synthesis in liver cell cultures from CBA, C57Bl/6j and AKR adult male mice was studied autoradiographically. Ultra-violet radiation (254 nm; 1.5-36 J/m2) triggered on an active unscheduled DNA synthesis in all cell cultures studied. The levels of unscheduled DNA synthesis in the liver cell nuclei of the spontaneous hepatocarcinogenesis-susceptible strain (CBA) and relatively, resistant ones (C57Bl/6j and AKR) were similar. It is suggested that the susceptibility to hepatocarcinogenesis in different murine strains is determined by such parameters as DNA damage and repair (stage of initiation) as well as factors peculiar to the stage of promotion.