The Changes and Significance of VEGF Expression after Focal Cerebral Ischemic Reperfusion in Rats

Objective To investigate the changes and significance of vascular endothelial growth factor(VEGF)expression in rats following cerebral ischemia/reperfusion.Methods healthy male Wistar rats 60 and weighing 250～300 g,were randomly divided into the control group,sham group,then 2 h focal cerebral ischemia/reperfusion 0,1,3,6,9,12,24,72 h,1,2 week and a total of 12 groups,each with five rats.The models of middle cerebral artery occlusion/reperfusion(MCAO/R)were established by an intraluminal filament method.In the corresponding time points,the brain were made coronal slices and to be taken into HE and immunohistochemical staining.Results in the HE staining,neuron degeneration,tissue edema and cerebral infarction can been seen in brain after ischemic/reperfusion.In immunohistochemisty staining:The VEGF expression in endothelia,neuron and glia increase at 2 h after ischemia.The expression in endothelia reaches top at 24-72 h after reperfusion,then decreases after 7 days,and still more than normal at 2 weeks.The expression in neuron and glia reaches top at 9-12 h,decreases at 24-72 h,and be normal before 1 week after reperfusion.Conclusions the expression of VEGF increase in endothelia,neuron and glia after ischemic/reperfusion but has different expression phase which indicated that the VEGF expression take part in the pathophysilogical process of cerebral ischemia by different ways.