Study Of Different Frequency Electroacupuncture Effects On Rat Synaptic Plasticity Of Hippocampal Neurons In Alzheimer’s Disease

Objective:To study the difference frequencies electro-acupuncture improving the function of memory and synaptic morphological plasticity of Alzheimer,s disease rats Methods:48 healthy wistar rats were Selected by Morris systerm and Randomly divided into six group.the AD model was established by inject Aβ1-42 into the two side lateral cerebral ventricle.2Hz and 50 Hz electro-acupuncture group were treated by “ Baihui ”,“Shenshu”two point.Two electro-acupuncture group were treated once a day,for two weeks, a total of 2 courses,during the two courses one day for rest.The Sham acupuncture group was used same point like two electro-acupuncture group but didn,t got electricity and just touch the skin.The sham operation group was given 0.9%Nacl injiecting into two side lateral cerebral ventricle.After treatment Morris water maze tests were investgated to detect memory function and electron microscope were used to observe the changes of the curvature of synaptic interface, the thickness of Post synaptic density, the width of synaptic cleft and the Percentage of Perforated synapses. Results:The AD model was successfully made by injecting Aβ1-42 into two side lateral cerebral ventricle.The result of Morris water maze tests:①Place navigation test:Compared to AD model group and sham acupuncture group the average escape latency of two electro-acupuncture group were shoter(P<0.01) but still longer than Normal group and sham operation group(P<0.01). There was no significant difference between nomal group and sham operation group( P > 0.05).The average escape latency of 50 Hz electroacupuncture group was shorter than 2Hz group(P<0.01).②Spatial probe test: Compared to AD model group,two electro-acupuncture group, the fist time of spatial probing the former platform were shorter and the number of spanning the former platform increased(P<0.01);And Compared to 2Hz electro-acupuncture group, the 50 Hz electro-acupuncture group, the fist time of spatial probing the former platform were shorter and the number of spanning the former platform increased(P<0.01)Electron microscope show that compared to model group,the Percentage of Perforated synapses was inerease(P<0.01), the curvature of synaptic interface was inereased(P<0.01), the width of synaptic cleft was decreased(P<0.01), the thickness of Post synaptic density was inereased(P<0.01)in two electro-acupuncture groups and the synaptic morphological plasticity in 50 Hz electro-acupuncture group changed obvious than 2Hz electro-acupuncture group(P<0.05). Conclusion:Electro-acupuncture can adjust hippocampal synaptic morphol ogical plasticity and the function of learning and memory could be improved.All of the result relevant to frequency.