RESUMO
The aim of the study was to establish the dependence of memory processes and learning ability in gamma-irradiated white mice on the age and period after irradiation. The 3-month and 1-year-old male mice (Mus musculus) were used in the study. Mice whole-body irradiation was performed at a dose of 5 Gy with 137Cs by using a "Gamma-capsule-2". Spatial learning and formation of memory were estimated in the elevated-type multi-way maze and elevated plus-maze. Experiments were carried out 48 hours and 30 days after irradiation for seven days (five trials each day). The number of errors (deviations from optimal trajectory) and total time for crossing the maze were calculated. The results of the study indicate that ionizing irradiation with a total dose of 5 Gy results in a delayed spatial learning process, causes spatial memory and behavior changes in different age groups of animals - aged mice turned out to be more radio-resistant. Age-related radio-resistance plays an especially major role in the early stage of post-radiation recovery. Though, the late radiation aging effect is especially pronounced in young animals.
