Abstract: [Abstract] Objective To examinate the effect of resveratrol on expression of synaptophysin after cerebral ischemia/reperfusion injury in rats. Methods 60 male Sprague-Dawley rats were divided into sham, ischemic control and resveratrol group. Each group is 20 rats. The rats were treated with resveratrol or ethyl alcohol by intraperitoneally for 7 consecutive days after 3 h for MCAO. At 24 h after MCAO/R, TTC assay examinated cerebral infarction volume and dry and wet weight method tested moisture content in brain tissue. At 24 h, 7 d and 14 d after MCAO/R, we examinated the neurological function score with Bederson score and the protein expression of synaptophysin in ischemic cortex with immunohistochemistry and Western blot. Results The infarction volumes in the control and resveratrol group were significantly higher than in the sham group (P < 0. 05), and it was significantly lower in the resveratrol group than in the control group (P < 0. 05).Brain water contents in the control and resveratrol group were significantly higher than in the sham group (P < 0. 05), and it was significantly lower in the resveratrol group than in the control group (P < 0. 05). The neurological function score in the control and resveratrol group were significantly higher than in the sham group at 24 h, 7 d and 14 d (P < 0. 05), and it was significantly lower in the resveratrol group than in the control group (P < 0. 05). Immunohistochemistry display that the positive expression of synaptophysin in ischemic cortex in the control group were reduced at 24 h, and increased gradually at 7 d and 14 d, but were significantly lower than in the sham group. After resveratrol treatment, it was significantly higher than in the control group at each point time, and was highest at 14 d. Western blot assay showed that the protein expression of synaptophysin in the control group was significantly lower than in the sham group at 24 h, 7 d and 14 d after MCAO/R (P < 0. 05), but gradually increased at 7 d and 14 d. After resveratrol treatment, it was significantly enhanced than in the control group at each point time (P < 0. 05), and was strongest at 14 d. Conclusion Resveratrol treatment can enhance the expression of synaptophysin and improve neurological function.

Key words: Resveratrol, Cerebral ischemia/reperfusion , Synaptophysin , Expression , Rat