Assessment of heterogeneity of rodents from laboratory colonies and a natural population by the criterion of radioresistance under stress

Studies on 600 animals (inbred and outbred laboratory mice and bank voles from a natural population) revealed differences in their response to equal (by LD50/30) gamma-radiation doses received against a background of drug-induced stress: the period of mortality significantly decreased in inbred mice, did not differ from the control in outbred mice, and increased in voles. At the same time, preliminary exposure to stress did not lead to significant changes in the proportion of animals that died from irradiation. The data obtained are interpreted as evidence of the leading role of the genotype in radioresistance and of the validity of the corresponding approach to the assessment of heterogeneity of laboratory colonies and natural populations of rodents.