The Effect of Aerobic Exercise on Spatial Learning and Memory Ability and Expression of NCAM in Hippocampus during the Aging Process of Rats

Objective:To discuss the effect of aerobic exercise intervention on aging rats, the spatial learning and memory abilities and the expression of Neural cell adhesion molecule in hippocampus.Methods:48male SD rats were divided into 3groups at random:control group (C, n=16) , D-galactose aging model group (D, n=16) and D-galactose to aging + aerobic exercise intervention group (DS, n=16) .After 6weeks, each group were divided into two groups randomly:one group fed naturally (N) , another group underwent Morris water maze experiment (M) for 7days.Whole groups were recorded as:CN (n=8) , DN (n=8) , DSN (n=8) , CM (n=8) , DM (n=8) and DSM (n=8) .At the end of 7th week, all rats were killed and the cerebral cortex SOD, gsh-px and MDA content were tested;The expression of NCAM gene in hippocampus was detected by Real-time PCR and Western blotting.Results:When compared to the rats in group C, which in group D show obvious symptoms of aging, such as depressed, sluggish, sleepiness, serious hair loss and so on.The SOD and gsh-px activity of rat in group D is lower than that of group C (P<0.01) , while MDA content is significantly higher (P<0.01) .However, rats in Group DSN have higher SOD and gsh-px activity (P<0.01) and lower MDA (P<0.05) than that of Group DN.During the period of Morris water maze training, all rats showed a shorter incubation period from day 1to day 6.The number that rats go through the platform in group DSM was significantly more than that of group DM (P<0.05) .The expression of NCAM in hippocampal in group D was very significantly lower than that of group C (P<0.05) , furthermore, the expression of NCAM in hippocampal in group DSM is very significantly higher than group DM (P<0.01) .Conclusion:1) The aging process with aerobic exercise intervention can up-regulate the activity of SOD and gsh-px, meanwhile inhibit the production of MDA;improve the ability of spatial learning and memory of rats;2) The im-58 provement of learning and memory may be associated with up-regulation of NCAM gene expression.