Features of the Effects of Exposure to 90–170 MeV Proton Radiation on the Blood-Forming Organs in Mice under Total Irradiation with Proton Pencil Scanning Beam Depending on the Linear Energy Transfer of Particles

The effects on induction of cytogenetic damage to mouse bone marrow, generation of reactive oxygen species by whole blood cells, and on the thymus and spleen from exposure of mice to total-body proton radiation before and at the Bragg peak with a dose deposition of 0.1–1.5 Gy were investigated depending on the linear rate of energy loss. It was found that the level of polychromatophilic erythrocytes with micronuclei at all doses of proton radiation at the Bragg peak with the linear energy transfer 2.5 keV/μm was close to that of polychromatophilic erythrocytes with micronuclei for the corresponding doses of X-ray radiation with the linear rate of energy loss 2.0 keV/μm, and the level of cytogenetic damage induced by exposure to proton radiation up to the Bragg peak with the linear energy transfer 0.7 keV/μm was significantly lower. The coefficient of the relative biological effectiveness of proton irradiation calculated from the linear energy transfer by estimating micronuclei frequency at and before the Bragg peak was 1.15 and 0.63, respectively. Organ-specific differences in the patterns of pathophysiological effects on the thymus, spleen of mice and the state of the antioxidant system of blood cells depending on the linear energy transfer of protons were revealed by varying radiation doses.