RESUMO
Structural elements of the central nervous system--neurons, along with the higher neuroendocrine structures and the hypothalamus centres, show high sensitivity to a chronic action of low doses of ionizing radiation (IR) in view of their extreme enrichment by phospholipids and intensive supply by oxygen, creating favorable conditions for the development of oxidizing stress. Stressful influences cause negative emotions in the behaviour of animals manifested as fear or uneasiness. The study represents the results of comparative research into the behavioral reactions characterized by uneasiness in the Balb/c and C57bl/6 mice exposed to a chronic irradiation at low doses. The chitin-melanin-glucan complex from fungi Fomes fomentarius (ChMG) was approved as an adaptive agent. It has been shown that under identical conditions, deposition levels of radionuclides 137Cs and 90Sr are raised in mice with IR hypersensitivity--line Balb/c, in comparison with less radio sensitive mice--line C57bl/6. Simultaneously, Balb/c mice were observed to exhibit the signs of a more anxious behaviour in the new environment. Chronic external and internal radiation exposure to rare ionizing radiation at low doses promotes strengthening of anxiety and phobic reactions in mice with IR hypersensitivity. The use of ChMG in animals neutralized the increase in anxiety and phobic reactions after a prolonged irradiation, thus indicating the presence in ChMG of the anxiolitic activity along with the above mentioned powerful radiosorbent, antioxidant, gene protective and immunomodulatory properties.