Objective To study the effects of electroacupuncture (EA) on the proliferation and differentiation of neural stem cells (NSCs),and to explore any effect of EA in neurological rehabilitation and its mechanism.Methods Middle cerebral artery occlusion (MCAO) was used to establish a model of cerebral infarction in 120 Wistar rats.They were then randomly divided into a treatment group and a control group,both of which were further subdivided into 1,3,7,14,21 and 28 day sub-groups with 10 in each sub-group.Bromodeoxyuridine (Brdu) was given at the 1st,2nd,6th,13th,20th and 27th day to detect any proliferation and differentiation of NSCs.After 7 days the motor function of the two groups was evaluated using a beam walking test.Rats were sacrificed at the different time points and Brdu labeled cells and nestin-positive cells were determined by immunohistochemistry.The level of basic fibroblast growth factor-2 (FGF-2) mRNA was determined by in-situ hybridization.The results were analyzed using a micro-image analysis system.Results The Brdu-labeled cell counts and nestin-positive cells were significantly different between the treatment and control groups at each time point.Motor function improved significantly in the treatment group with EA stimulation compared with the control group,but there was no significant difference between the 21 day and 28 day sub-groups in the treatment group.The expression levels of bFGF-2 mRNA were significantly different between the treatment and control groups at the early time points (up to the 14th day).Conclusions EA can promote proliferation of NSCs and increase the expression of FGF-2 mRNA,particularly early after cerebral infarction.It may be one of mechanisms of EA's effectiveness in treating ischemic stroke.