Abstract:In order to explore the correlation of spatial learning and memory functions with aging and SytⅠlevel in hippocampus,three groups of Kunming mice (Mus musculus)at different ages (22 months,11 months and 6 months,respectively) were used. The ability of spatial learning and memory was evaluated by six-arm radial water maze ( RAWM ),the expression of Syt Ⅰ was detected by the immunohistochemistry method ( S-P method),and the data of RAWM and Syt Ⅰ relative content were analysed. It is showed that the average number of errors and latency during learning and memory phase was higher in the 22-month-old group than that in the middle-aged or young group (P < 0. 05),and that there was no significant difference between the middle- aged mice and young mice ( P > 0. 05 ). Meantime,the relative Syt Ⅰ amount in the DG and CA3 ofhippocampus in the 22-month-old mice was significantly higher than that in the middle-aged or young mice ( P < 0. 05). The positive correlation was confirmed between the relative level of Syt I in the DG and CA3 of hippocampus and the number of errors and latency during learning and memory phase (P < 0. 05). Therefore, the results indicate that age-related impairment of spatial learning and memory exists,and the amount of SytⅠ in hippocampus significantly increases with aging in Kunming mice, and that the amount of Syt Ⅰ in hippocampus may be involved in the age-related spatial cognitive impairment.