Delayed effects of chronic low-dose high linear energy transfer (LET) radiation on mice in vivo

In the present work, the delayed effects of chronic high linear energy transfer (LET) radiation in polychromatic erythrocytes (PCEs) of mice bone marrow were investigated in vivo. Irradiation of the two-month-old SHK white mongrel random-bred male mice was performed in the radiation field behind the concrete shield of the accelerator of 70 GeV protons to accumulate doses of 0.005-0.16 Gy. The dependence of the biological response on dose, adaptive response (AR) and genomic instability (GI) in F(1) and F(2) generations from males irradiated with doses of 0.005 and 0.16 Gy and from males exposed to combined action of immunomodulator-bendazol hydrochloride (BH) and of 0.16 Gy irradiation, were examined using the micronucleus formation test. The data demonstrated that irradiation of mice with these doses lead to an increase in the level of cytogenetic damage and induces no AR. With analysis of the bone marrow radiosensitivity to 1.5 Gy of X rays and the capacity to AR it was found that the chronic high-LET irradiation of parents induced the GI at least two generations. The combined exposure to BH and the dose of 0.16 Gy induces no AR in F(0) generation but induces AR in F(1) and F(2) offspring.