Effects of electro-acupuncture on proliferation of endogenous neural stem cells after focal cerebral ischemia in adult rats

Objective:To investigate the effects of electro-acupuncture(EA) on the proliferation of neural stem cells (NSCs) and neurogenesis in the regions of ischemic brain injury of rats and to explore the mechanism of EA in treating ischemic brain injury. Method:The model of permanent focal ischemia was made by heat-coagulation of the right middle cerebral artery(MCA) after craniotomy, and the rats were randomized into model group and EA group. After middle cerebral artery occlusion (MCAO), proliferating brain cells were labeled with bromodeoxyuridine (BrdU) and EA was applied to Dazhui and Baihui in EA group. At the 3rd, 7th, 14th and 21st days after cerebral ischemia rats(n=5) were killed and the number of proliferating cell was observed by Immunohistochemistry for BrdU. Result: BrdU-positive cells were found in cortex, dentate gyrus (DG), striaturn and subventricular zone (SVZ) at different time after cerebral ischemia, at the 7th day remarkably increased(P0.01). The number of BrdU-positive cells in EA group was more than that in model group at different time (P0.05 or P0.01). Conclusion: Ischemia can stimulate the proliferation of NSCs and the proliferation can be promoted by EA in interrelated regions after focal cerebral ischemia. It may be one of important mechanisms of EA in treating ischemic brain injury to enhance endogenous neurogenesis after ischemia.