[Effects of combined action of Cd and gamma radiation on DNA damage and repair in lymphoid tissues of mice].

The effect of combined treatment of Cd and gamma-irradiation on DNA damage and repair was studied in lymphoid tissues of mice using single-cell gel assay. Single i.p. injection of CdCl2 (1 mg Cd/kg body wt), 2 h prior to irradiation resulted in increasing of DNA lesions in peripheral blood lymphocytes(PBL) when compared to non-injected animals. However, the same treatment, 48 h prior to irradiation is shown to decrease DNA damage in PBL and splenocytes in comparison with untreated mice. In thymocytes maximal protective effect of Cd was determined when mice were irradiated in 24 h after injection. The protective effect observed is due to decreasing of initial level of DNA damage in thymocytes as well as acceleration of DNA repair in PBL and splenocytes.