Effect Of Electroacupuncture On Related Factors Of Synaptic Remodeling In EphrinB2 / EphB2 Signaling Pathway In MCAO Rats

Objective:We explored the possible mechanism and provide theoretical foundation of electric acupuncture treatment on cerebral ischemia injury by observing the changes of neural function defect scale, brain tissue histomorphology and cynapse reconstruction related factors in cortex around infarction of MCAO rats after electroacupuncture treatment on Ganshu, Shenshu points.METHOD:180healthy male Sprague-Dawley rats were randomly and equally divided into four groups:the sham-operated group, the model group, the acupuncture group and the nonacupuncture point group. Samples in all groups except those in the control group were duplicated into models of MCAO with Zea-longa modified thread-occlusion method. The acupuncture group and the nonacupuncture point group receive electroacupuncture for30minutes in everyday morning, while the other two groups were only tied up without electroacupuncture for30minutes in the same time.After MCAO successfully established, the neurological deficit of rats were evaluated by neurological function deficits scale, morphological changes of brain tissue was measured by TTC staining method, the expression changes of EphB2and ephrinB2in the peripheries of cortical infarct focus was tested by immunohistochemical staining, the location and expression of EphB2+/PSD-95+was observed by double immunofluorescent staining, and the expression of EphB2,ephrinB2,Rac-land MAP-2was measured by Western blot method at each time point in every group.Results:1After MCAO successfully established, the highest score of neurological function deficits was appeared on3-day, the score was tapered as time goes on. The acupuncture group were significantly reduced compared with model group and nonacupuncture point group. The changes of infarct area were closely related with neurological function deficits score.2. The number of EphB2/ephrinB2positive cells in the peripheries of cortical infarct focus of MCAO rats were decreased significantly on3-day and were gradually returned to baseline levels on21-day. The number of EphB2/ephrinB2positive cells of the acupuncture group were significantly increased compared with model group and nonacupuncture point group and exceeded that of the sham group.3. The confocal laser scanning microscope had observed part of the coexistence phenomenon of EphB2and PSD-95in the peripheries of cortical infarct focus was observed by double immunofluorescent staining and were gradually increased with the time, especially in the acupuncture group.4. The expression changes of Rac-1and MAP-2, which were the synaptic plasticity related factors in ephrinB2/EphB2pathway, were gradually increased with the time and reached the level of the sham group. The expression of Rac-1and MAP-2were significantly increased compared with model group and nonacupuncture point group.Conclusion:1. The electroacupuncture treatment on Ganshu, Shenshu points increase the expression of ephrinB2, EphB2, Rac-1and MAP-2and upregulation PSD-95in the peripheries of cortical infarct focus of MCAO rats.2. The electroacupuncture treatment on Ganshu, Shenshu points significantly increases the neurological function as activating ephrinB2/EphB2pathway and promoting synaptic plasticity. The activation of ephrinB2/EphB2pathway may promote synaptic plasticity.3. The gradually increase of the synaptic plasticity related factors of ephrinB2/EphB2pathway in the peripheries of cortical infarct focus after MCAO established was may due to the upregulation of synaptic plasticity, which could be promoted by the electroacupuncture treatment on Ganshu, Shenshu points.