Low-Intensity Femtosecond Radiation Activates the Natural Defenses of Mice in vivo

The possibility of induction of cytogenetic damage in the bone marrow, changes in the cellularity of lymphoid organs and blood composition in mice irradiated with low-intensity femtosecond laser radiation at a power flux density of 5.1, 10.4, and 52 mJ/cm² (0.5 mW for 5, 10, and 50 s) in vivo was shown. Using the radiation adaptive response test (0.1 Gy + 1.5 Gy), it was found that, when mice were exposed to femtosecond laser radiation in high doses, the body's natural defenses were activated in the same narrow range of energy flux density (2-16 mJ/cm²) as in the case of X-ray irradiation in a dose of 0.1 Gy (4 mJ/cm²). The data obtained suggest a similar mechanism of activation of the body's natural defense upon exposure to low doses of both ionizing and non-ionizing radiation.