The Mechanism Of Electroacupuncture On Back-Shu Points Improving Learning And Memory Ability Of VD Rats

Objective: Observing the influence of electroacupuncture on behavioral study, converse messenger molecule of LTP, pathological morphological study of nerve cell of hippocampus in brain, and ultra structure of synapse in CA3 area of vascular dementia (VD) rats to research the mechanism that EA improve learning and memory ability of VD ratsMethod: The VD rats were modeled with method of global ischemia reperfusion by 4 vascular occlusion (4-vo). Morris water tests were used for behavioral study. The nitric oxide in brain was measured with spectrophotometry. The content of CO in plasma was measured by a two-wavelength spectrophotometer. The TXB₂ and 6-keto-PGF1αin plasma was estimated by radioimmunoassay. The changes of the ultra structure in CA3 sector of the hippocampus were studied with transmission electron microscope and Automatic Picture Analysis System.Results: The VD group animals needed more escape time than the control group, and they did not swim longer in platform quadrant than in the others in the Morris water tests. The content of nitric oxide in cerebrum was higher than the others. The content of CO in plasma was higher than the others. The content of TXB₂ in plasma had increased; and the content of 6-keto-PGF1αin plasma of them had decreased. The cells were atrophied and dwindled. The front and back membrane of the synapses was illegible. The numerical density (NA) , surface density (Sv) and volume density (Vv) of synapses in CA3 sector of the hippocampus in VD rats were decreased significantly. The clearance, PSD and interphase curvature of synapses in CA3 sector of the hippocampus in VD rats were decreased significantly. In EA group, the animals cut the escape time mostly and they swam more times in platform quadrant than in other three quadrants. The content of nitric oxide in cerebrum was obviously decreased. The content of CO in plasma was decreased. The content of TXB₂ in plasma had decreased; and the content of 6-keto-PGF1αin plasma of them had increased. The modality configuration of cells in CA3 sector of the hippocampus was normal, and the normal and abnormal chromatin was obvious. The configuration of endoplasmic reticulum,chondriosome and synapses was normal. The front and back membrane of the synapses was clear. The NA,Sv,and Vv of synapses in CA3 sector of the hippocampus were increased significantly. The interphase curvature, cleft and PSD of synapses in CA3 sector of the hippocampus were increased significantly.Conclusion: Electropuncture on back-shu points can improve learning and memory ability of VD rats, inhibit the increase of the content of nitric oxide in cerebrum, CO and TXB2 in plasma, and accelerate the increase of the content of 6-keto-PGF1αin plasma, all of which were concerned with the process of the damage of nerve cells of VD model rats, so it can reduce the occurrence of vascular dementia. Electroacupuncture on back-shu points could restrain the disappearance of nerve cells and synapses in CA3 sector of the hippocampus, and meliorate the structure parameter of synapses.