Effects Of Different Load Exercise On Learning And Memory Ability And BDNF Expression In Hippocampus Of Rats

Abstract:Objective:By studying the change between rats that got exercises of different loads,determine the gene expression of BDNF in hippocampus and discuss influence of different loads of exercises on the gene expression of BDNF and the capability of learning and memory. Methods:48SD rats were divided into Swimming and Nature gourp (N) and Swimming and Morris group(M) randomly.After a7-week swimming excercise,Group N were decapitated to death and got the brain tissue;Group M had a10-day Morris water maze behavior excercise and a space exploration experiment after the7-week excercies,then also decapitated to death and got the brain tissue.According to the different loads of excercises,each major group was divided into3minor groups(each minor groups contains8rats).Group N was divided into Control and Nature group(CN),Middle load Swimming and Nature group(MN)and gourp Over load Swimming and Nature(ON).Group M was divided into Control and Morris group(CM),Middle laod Swimming and Morris group(MM) and Over laod Swimming and Morrise group (OM).By analysing the gene expression of BDNF quantitativly by Real-tiem PCR and Western-blotting.Results:(1)Rats of every group had weights increased,control groups had apparent higher weights increased than over load exercise groups,and there was a obvious difference between these two groups(p<0.01).(2)In the space exploration experiment,as the learing days incresed, distance of rats swiming in the water maze of every groups were all reducing significantly.In2nd day,total distances of Group MM were apparently shorter than Group OM,and there was a obvious difference between these two groups(p<0.01) while contrary,there was no obvious difference between Group CM and Group OM(p>0.05).The comparison of Space exploration experiments on rats through the number of platforms, MM group was significantly more than CM group and OM group, and there was significant difference (p<0.05).(3)After different load exersices.gene expression of Hippocampal BDNF mRNA of rats in Middle load exercise group was higher than control groups and Over load exercise groups,which diffrence was not so obivious.(4)Protein expression of Hippocampal BDNF of rats in Group MN was higher than Group CN and Group ON(p<0.01),protein expression of Hippocampal BDNF of rats in Group MM was obvious higher than Group CM(p<0.01),protein expression of Hippocampal BDNF of rats in Group OM was significantly higher than Group CM and Group MM.Conclusion:(1)Long-term middle load exercise induces the rise of the gene and protein expression of hippocampal BDNF mRNA.Long-term middle load exercise may play a catalytic role in learning and memory by raising the level of BDNF gene expression.(2)Over load exercise induces the inconsistent between hippocampal mRNA gene expression and the protein expression of rats whose reason was probably the death of the delayed neuron,the raise of protein expression of BDNF may involve in learning and memory capability.