Different Frequency Electrical Research On Cerebral Ischemia Synaptic Structural Plasticity Effects

Objective:To observe the effects of electroacupuncture at different frequencies on the synaptic plasticity in the ischemic area of cerebral infarction rats, and to explore the mechanism of electroacupuncture in the treatment of cerebral ischemia.Methods:60 male SD rats, randomly divided into for six groups:blank group, sham operation group, model group,2 Hz EA group,50 Hz EA group, 100Hz EA group,10 rats in each group. According to the suture method preparing rat middle cerebral artery occlusion (MCAO) model of cerebral infarction. Blank group will not be any direct disposal broken materials, the sham operation group only surgery without modeling, model group, the animal model not dispose of any, blank group, sham operation group and model group rats, but in electro acupuncture group was treated the same time be tied and fixed, not to be acupuncture therapy.2Hz EA group,50 Hz EA group, 100Hz EA group were acupuncture, cerebral infarction, rat suffering from side "top three" acupoint and "Waiguan acupoint, and according to the corresponding group separately to 2Hz,50Hz, 100Hz wave type for continuous wave 1mA current, treatment once a day every 20 minutes. At specific time points after treatment, the screen experiments on rats function of upper limb nerve injury score; rats in each group after the last treatment and scores were collected, materials and immunohisto chemical method for detection of rat cerebral cortex synaptic membrane density related protein PSD-95 positive cells expression, by transmission electron microscopy observation in rats with focal cerebral ischemia of synaptic structure g surface density of synapses in Su Xizhong number density and synaptic contact zone.Result:1.The effect of Electroacupuncture on the behavior of MCAO model rats: the specific time points after operation, the model group and the blank group were compared, the differences were statistically significant (P<0.01). Compared with the model group, there was no significant difference between the 1D,3D, and 7d EA groups (P>0.05). Fourteenth,21d, electro acupuncture group and model group, the difference was significant, there was statistical significance (P<0.05), electro acupuncture group compared with the blank group, the difference was not statistically significant (P>0.05).2.By transmission electron microscope observation showed:blank group and sham operation group rats of cerebral ischemic cortex can clearly see many synapses in the neuropil widely and evenly distributed, synaptic before and after membrane structure integrity and clear, silhouette visible. Pre-and in the posterior region of the organelles rich and clearly visible, synaptic axon terminals synapse enlargement by the formation of the ball that shoots foot containing large numbers of synaptic vesicles, most of which is complete round or oval in shape, distribution of mean and dense. Compared with the presynaptic membrane, the postsynaptic membrane was thicker and thicker. In the model group, the number density of synapses and the density of the synaptic contact area were significantly reduced, and the cytoskeleton structure of the neural processes also disappeared. Remarkable changes in synaptic structure:part of axons appear swollen and electron density decreased significantly or even a huge vacuole; Electroacupuncture group and blank group compared to the number of synapses was significantly reduced and the presynaptic component of the outline of the structure and the ambiguity of cytoskeleton structure defect, scattered phenomenon, synaptic connections with also obviously reduced. With end of the electro acupuncture treatment, the recovery of cerebral ischemic injury, electroacupuncture group and blank control group comparison of synaptic Trend Micro structure defect than before to reduce, the number of synapses have Zo, synaptic structure compared with the model group, the clear and complete and EA group recovery levels were significantly higher than model group, difference significantly.3.The positive expression of PSD-95 in the ischemic area of rats after electroacupuncture:the IOD PSD-95 value increased and the IOD PSD-95 value decreased in the ischemic area after cerebral ischemia. Blank group compared with those in the sham operated group, but there was no significant difference, had no statistical significance (P>0.05); model group, EA group and blank group compared significant difference, was statistically significant (P<0.05); the rest of the group and the model group compared significant difference, was statistically significant (P<0.05); electric acupuncture group, the difference was not obvious, had no statistical significance (P> 0.05).Conclusion:1.Electroacupuncture can significantly improve the neurological behavior scores of rats with cerebral infarction, and promote the recovery of motor function of the upper limb in rats with cerebral infarction.2.Electroacupuncture has the effect of nerve repair and protection on cerebral infarction, and its mechanism may be related to the changes of the number density and the surface density of synaptic contacts in the synaptic structure plasticity in the ischemic area.3.Electro acupuncture has the function of nerve repair and protection for cerebral infarction, and its mechanism may be related to the increase of the positive expression of postsynaptic membrane protein PSD-95 in the synaptic structure plasticity of the ischemic region.