Comparative Analysis of Behavioral Reactions and Morphological Changes in the Rat Brain After Exposure to Ionizing Radiation with Different Physical Characteristics.

The aim of this research was to study behavioral reactions and morphological changes in the brain of adult female Sprague Dawley rats after exposure to 170 MeV and 70 MeV protons and gamma radiation (60Co) at a dose of 1 Gy. The analysis of the behavioral reactions in the T-maze showed that exposure to ionizing radiation with different LETs led to an increase in number of repeated entries into the arms of the maze in the spontaneous alternation test. In the Open Field test a decrease in overall motor activity in the group of irradiated animals (70 MeV protons at the Bragg peak) was observed. A decrease in the number of standing positions was seen in all groups of irradiated animals. Morphological analysis showed the development of early amyloidosis, autolysis of the ependymal layer, an increase in the number of neurodegenerative changes in various structures of the brain, and the development of neuronal hypertrophy on the 30th day after irradiation in the cerebellum and hippocampal hilus. Exposure to protons at a dose of 1 Gy leads to the development of structural and functional disorders of the central nervous system of animals on the 30th day after irradiation. These data indicate a damage of short-term memory, a decrease in motor activity and exploratory behavior of animals. With an increase in LET, there is an increase in the number of amyloid plaques in the forebrain of rats, autolysis of the ependymal layer of the ventricles, and the development of dystrophic changes. Investigations of behavioral reactions and morphological changes in various parts of the brain of adult rats on the 30th day after influence of ionizing radiation with different physical characteristics at a dose of 1 Gy. Various negative patho-morphological and cognitive-behavioral changes observed.