Objective:To observe the effects of electroacupuncture(EA)with three frequencies(100 Hz,2 Hz,and 2 Hz/100 Hz)on the apoptosis of neurons and c-Jun N-terminal kinase(JNK)signaling pathway in the hippocampus of rats wit...Objective:To observe the effects of electroacupuncture(EA)with three frequencies(100 Hz,2 Hz,and 2 Hz/100 Hz)on the apoptosis of neurons and c-Jun N-terminal kinase(JNK)signaling pathway in the hippocampus of rats with vascular dementia(VD),and explore the mechanism of EA intervention for VD.Methods:Fifty male Sprague-Dawley rats were randomly divided into a model group,a sham operation group,a 100 Hz EA group,a 2 Hz EA group,and a 2 Hz/100 Hz EA group,with ten rats in each group.The VD model rats were established by repeated ischemia-reperfusion of bilateral common carotid arteries.The rats in the EA groups received EA intervention at Baihui(GV20),Dazhui(GV14),Geshu(BL17)and Zusanli(ST36),once a day for 14 d.Afterward,Morris water maze was used to examine the learning and memory performances of the rats in each group,hematoxylin-eosin staining to observe the histomorphological changes in the hippocampal CA1 region,terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling to test the apoptosis of neurons in the hippocampal CA1 region,and Western blot to detect the protein expression levels of JNK,phosphorylated JNK(p-JNK),Caspase-8,and Caspase-3 in the hippocampus tissue.Results:Compared with the sham operation group,the escape latency of the model group in water maze test was prolonged;the number of crossing the original platform was decreased(P<0.01);the hippocampal neurons were severely damaged and the number of surviving neurons was decreased(P<0.01),whereas the number of apoptotic neurons was increased(P<0.01);the protein expression levels of JNK,p-JNK,Caspase-8,and Caspase-3 in the hippocampus were significantly increased(P<0.01).Compared with the model group,the escape latency of each EA group was significantly shortened;the number of crossing the original platform was significantly increased(P<0.01);the damage of hippocampal neurons was alleviated,the number of surviving neurons was increased(P<0.01),and the number of apoptotic neurons was decreased(P<0.01);the protein expression levels of JNK,p-JNK,Caspase-8,and Caspase-3 in the hippocampus were decreased(P<0.01).The results in the 2 Hz EA group and the 2 Hz/100 Hz EA group were superior to those in the 100 Hz EA group.Conclusion:EA with the three frequencies(100 Hz,2 Hz,and 2 Hz/100 Hz)can improve the learning and memory performances in VD rats subjected to ischemia-reperfusion,its mechanism may be related to the inhibition of neuronal apoptosis and the regulation of the related protein expression of JNK signaling pathway,and the intervention effects of EA with 2 Hz and 2 Hz/100 Hz are more significant.展开更多
文摘Objective:To observe the effects of electroacupuncture(EA)with three frequencies(100 Hz,2 Hz,and 2 Hz/100 Hz)on the apoptosis of neurons and c-Jun N-terminal kinase(JNK)signaling pathway in the hippocampus of rats with vascular dementia(VD),and explore the mechanism of EA intervention for VD.Methods:Fifty male Sprague-Dawley rats were randomly divided into a model group,a sham operation group,a 100 Hz EA group,a 2 Hz EA group,and a 2 Hz/100 Hz EA group,with ten rats in each group.The VD model rats were established by repeated ischemia-reperfusion of bilateral common carotid arteries.The rats in the EA groups received EA intervention at Baihui(GV20),Dazhui(GV14),Geshu(BL17)and Zusanli(ST36),once a day for 14 d.Afterward,Morris water maze was used to examine the learning and memory performances of the rats in each group,hematoxylin-eosin staining to observe the histomorphological changes in the hippocampal CA1 region,terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling to test the apoptosis of neurons in the hippocampal CA1 region,and Western blot to detect the protein expression levels of JNK,phosphorylated JNK(p-JNK),Caspase-8,and Caspase-3 in the hippocampus tissue.Results:Compared with the sham operation group,the escape latency of the model group in water maze test was prolonged;the number of crossing the original platform was decreased(P<0.01);the hippocampal neurons were severely damaged and the number of surviving neurons was decreased(P<0.01),whereas the number of apoptotic neurons was increased(P<0.01);the protein expression levels of JNK,p-JNK,Caspase-8,and Caspase-3 in the hippocampus were significantly increased(P<0.01).Compared with the model group,the escape latency of each EA group was significantly shortened;the number of crossing the original platform was significantly increased(P<0.01);the damage of hippocampal neurons was alleviated,the number of surviving neurons was increased(P<0.01),and the number of apoptotic neurons was decreased(P<0.01);the protein expression levels of JNK,p-JNK,Caspase-8,and Caspase-3 in the hippocampus were decreased(P<0.01).The results in the 2 Hz EA group and the 2 Hz/100 Hz EA group were superior to those in the 100 Hz EA group.Conclusion:EA with the three frequencies(100 Hz,2 Hz,and 2 Hz/100 Hz)can improve the learning and memory performances in VD rats subjected to ischemia-reperfusion,its mechanism may be related to the inhibition of neuronal apoptosis and the regulation of the related protein expression of JNK signaling pathway,and the intervention effects of EA with 2 Hz and 2 Hz/100 Hz are more significant.
