[Mitigation of mice radiation damage after acute and prolonged γ-irradiation by a laser device]

Effects of 7 Gy 60Co γ-radiation (acute and prolonged exposure), and combined exposure to 650 nm laser and γ-radiation on survival, peripheral blood, karyocyte count and mitotic index of bone marrow cells were studied in young C57BL/6 mice. All mice died following acute γ-irradiation at the dose rate of 1.14 Gy/min for 5 days or combined exposure for 11 days. Thirty percent survival from prolonged exposure to the dose rate of 0.027 Gy/min was observed after 19-day γ- and 38-day combined irradiation. Peripheral blood parameters did not differ significantly after acute and prolonged exposure; however, hyperchromemia was observed in mice after 24 hours of acute γ-irradiation. The count of mitoses per 1000 nucleus-containing BM cells evidenced that BM was virtually collapsed after 72 hours since the acute γ-exposure. It was demonstrated that laser can manage protection from a broad range of ionizing radiation doses and mitigate the adverse effects of equally acute and prolonged radiation exposure.