Objective:To explore the neuro-protective effect of limb remote ischemic post-conditioning(RIP)on middle cerebral artery occlusion(MCAO)after RIP. Methods:Totally 98 healthy adult male SD rats were randomly divided into three groups:sham group(n=14)

control group(n=14)and limb remote ischemic post-conditioning group(RIP group

n=14). After ischemia and reperfusion

control group and RIP group were further divided into three subgroups:12

24

72 h groups. The neuro-protective effects of limb remote ischemic post-conditioning was assessed using Longa way of neurological deficit scores at 12

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72 h. The percent of cerebral infarction volume at each point were also determined in time by HE staining and magnetic resonance imaging. Vascular endothelial growth factor(VEGF)and matrix metalloproteinase-9(MMP-9)expression in ischemic penumbra was detected by immunohistochemistry staining. Results:The neurological function scores were decreased in 24 h group than in control group(P=0.000). The volume of cerebral infarction in RIP groups reduced at 12

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72 h after ischemic compared with that in control group. VEGF expression was significantly increased but MMP-9 expression was significantly decreased in RIP group than in control group(P=0.0000;P=0.000).Conclusion:RIP reduces neurological deficit scores at 24 h

decreases percent of infarction volume from 12 h to 72 h after ischemia

thus alleviates cerebral ischemia reperfusion injury. Significantly lower expressions of MMP-9 and higher expressions of VEGF after MCAO are observed in ischemic penumbra in RIP group

suggesting that decreased MMP-9 and increased VEGF expressions are tightly associated with the neuro-protective effect of RIP.