Abstract: Objective To investigate the effects of low frequency stimulation (LFS) on proliferation and angiogenesis of neural stem cells (NSC) in cerebral infarction side in rats. Methods The rats with permanent middle cerebral artery occlusion (MCAO) were randomly divided into sham-operation group, control group and LFS group, each group was divided into 7 days and 14 days subgroups with 12 rats in each subgroup. LFS therapy was started 2 days after operation. The degree of nerve function defect was evaluated with Neurological Severity
Score (NSS), and the 5-bromodeoxy-dine (BrdU) positive cells in the subventricular zone (SVZ) of cerebral infarction side were detected with immunofluorescence. Stromal cell-derived factor 1(SDF-1) and vascular endothelial growth factor (VEGF) in infarction side were detected with enzyme-linked immunosorbent assay (ELISA). Results The NSS score was lower in the LFS group than in the control group and the sham-operation group 14 days after surgery (P<0.01). The number of BrdU positive cells, the content of SDF-1 and VEGF in the ischemic side were more in the LFS group than in the other groups (P<0.01) after treatment. Conclusion LFS can improve the neurological function in rats with acute cerebral infarction, which may associate with activating SDF-1/CXCR4 axis.

Key words: low frequency stimulation, stromal cell-derived factor-1, 5-bromodeoxy-dine, vascular endothelial growth factor, rats