[Radiation-induced adaptive response in children and effect of external and internal factors]

434 children 3-13 old age and 4 adult people 20-40 old age have been investigated by the use of micronucleus (MN) assay and cytokinetical block by cytochalasin B on the ability to the adaptive response (AR). The frequency of lymphocytes with MN was scored in 1000 binucleated cells after irradiation in challenge dose of 1 Gy and together in adaptive (0.05 Gy) and challenge doses. The significance of differences have been determined by chi 2 criteria. It was shown that definite AR was determined in approximately 20 percent of "normal" children, when in adult population--in approximately 50 percent cases. The part of children with AR decreases in the groups of children with defects of development, with mentally deficiencies, with hard heredity (the parents are the chronic alcoholics), with the high pressure of genotoxic agents. It was discovered that in about the half of the children there is opposite effect observed-irradiation in adaptive dose induce the increasing of radiosensitivity; this effect is insignificantly expressed in adult people. The problems of genetic determination of AR, influence of different factors, the significance of AR as the phenomen of protection from extremal action have been discussed.