title: The effect of dose fractionation on gamma-radiation induced mutations in mammalian cells.
abstract: The lethal and mutagenic effects of single and fractionated doses of gamma-radiation were studied in V79-4 Chinese hamster cells, as dose fractionation is of interest in radiation protection studies. The results show that the induction of 8-azaguanine resistant (Agr) mutants has a non-linear dose response curve following single doses of radiation. The lethal and mutagenic effects of fractionated doses were always less than if the radiation was given in a single dose. Any change in treatment which led to an increase in survival also led to a decrease in induced mutation frequency. There was a relationship between mutation and survival which was independent of the number of fractions in which the radiation was given. This could be of consequence in radiological protection.
mesh_terms: D001375:Azaguanine / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects*; D002478:Cells, Cultured / Q000187:drug effects / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004351:Drug Resistance / Q000528:radiation effects; D005720:Gamma Rays; D009154:Mutation / Q000528:radiation effects*; D011839:Radiation, Ionizing
chemical_list: D001375:Azaguanine