Effect Of Electroacupuncture On JNK Signaling Pathway In Hippocampus Of Rats With Vascular Dementia

Objective: This paper aims to observe the effects by electroacupuncture on the behavior of Vascular Dementia(VD)rats,the pathomorphology of hippocampal CA1 area and the apoptosis and JNK,p-JNK,Caspase-3 and Caspase-8 proteins in hippocampal neurons which related with apoptosis.We observing expression of electroacupuncture to explore the intervention effects,mechanism of action and frequency correlation of VD,for providing an objective basis for acupuncture clinical treatment of VD.Methods: The VD rat's modle needed to make a duplicate of ischemia and reperfusion of the Common Carotid Arteries(CCA).The surviving model rats were randomly divided into model group,nimodipine group,2 Hz electroacupuncture group,100 Hz electroacupuncture group and 2/100 Hz electroacupuncture group after modeling.In the electroacupuncture group,“Dazhui”,“Baihui”,“Housanli”(double),“Geshu”(double)points were connected with electroacupuncture and stimulated at 2Hz,100 Hz and 2/100 Hz respectively.We tested the rats' behavior by Morris water maze test on the 17 th day after modeling.The morphology of the neurons was observed by Nissl staining,and detection of neuronal apoptosis by TUNEL,the expressions of JNK,p-JNK,Caspase-8 and Caspase-3 in hippocampus were detected by Western Blot.Results: 1.Behavioral test: The escape latency of the model group was significantly longer than that of the sham operation group.The number of crossing the virtual platform was significantly reduced(P<0.01).Compared with the model group,the avoidance latency was shortened in each treatment group(P<0.01).2.Pathomorphological observation: In sham-operated group,the hippocampal cells were intact and Nissl bodies were abundant.In the model group,the cells were loose and disordered,and the number of Nissl bodies decreased significantly.Compared with model group,the number of Nissl bodies in each treatment group increased relatively,and the morphology of neuron cells also improved.3.TUNEL staining observation: The expression of TUNEL positive cells in the sham operation group was not obvious,and the expression of apoptosis-positive cells in the model group was significantly increased.The expression of apoptotic cells in each treatment groups were lower than that in the model group.4.Western Blot: Compared with the model group,the expression of JNK,p-JNK,Caspase-3 and Caspase-8 was decreased in every treatment group comparing with the model group(P<0.01).The electroacupuncture groups had no significant difference in reducing the expression of JNK(P>0.05).The 2Hz group and the 2/100 Hz group were more effective in reducing the expression of p-JNK and Caspase-8(P<0.01).The 2/100 Hz group was more effective than 2Hz group and 100 Hz group in reducing the expression of Caspase-3(P<0.05,P<0.01).Conclusion: Electroacupuncture can significantly alleviate the pathological damage caused by cerebral ischemia-reperfusion in hippocampal neurons of VD rats,and improve the learning and memory abilities of model rats.Its mechanism may be related to the reduction of JNK,p-JNK,Caspase-8,Caspase-3 protein expression by electroacupuncture,inhibition of JNK pathway-mediated apoptosis in hippocampal neurons of model rats,improvement of central nervous system function.And there are some differences in the intervention effects to different proteins of different electroacupuncture frequencies.