Study on enhancing cerebral ischemic tolerance by dl-3n-butyphthalide

OBJECTIVE To study the expression of glial fibrillary acidic protein(GFAP),basic fibroblast growth factor(bFGF) in the ischemic tolerance induced by focal cerebral ischemic preconditioning,and to explore the mechanisms of ischemic tolerance of butylphthalide.METHODS In this study,ischemic preconditioning(IP) was induced by intraluminal filament middle cerebral artery for 10 min.Middle cerebral artery occlusion(MCAO) was induced by intraluminal filament for 2 h after IP 72 h.30 SD rats were included and randomly divided into 3 groups: The(SS+MCAO) group only received 2 h MCAO followed by 22 h reperfusion with pretreatment of sham surgery 3 d before,focal ischemic preconditioning group(IP+MCAO) received 2 h MCAO followed by 22 h reperfusion with IP.The IP+NBP+MCAO group received 2 h MCAO followed by 22 h reperfusion with IP,during the time were given NBP every day.Each group was 10 SD rats.At 22 h perfusion end point,the infarct volume,histopathological changes with HE staining under a microscopy,the expression of GFAP and bFGF by using immunohistochemistry method were evaluated in each group.RESULTS The infarct volume of IP+NBP+MCAO group were significantly less than MCAO group and IP+MCAO group(P0.05).The pathological change was moderate detected in the brain of IP+NBP+MCAO group than the(SS+MCAO) group and the IP+MCAO.The number of GFAP and bFGF positive cells in the brain of IP+NBP+MCAO group,in which the morphological changes of astrocytes were detected,were significantly more than that in the IP+MCAO group(P0.05).CONCLUSION Focal cerebral ischemic preconditioning can provide brain protection and induce ischemic tolerance.Activating astrocyte and up-regulation of the expression of bFGF might play important roles in the induction of endogenous neuroprotection in the ischemic tolerance.And the butylphthalide can enchance the ischemic tolerance.