Expression of VEGF and VEGF mRNA after focal cerebral ischemia reperfusion in rats

Objective:To study the expression of vascular endothelial growth factor (VEGF) and VEGF mRNA after focal cerebral ischemia reperfusion in rats.Methods:MCAO (Middle Cerebral Artery Occlusion) models were set up in rats,and the rats were divided into six groups:control group,5 groups of ischemia for 2h then respective reperfusion for 6h,12h,24h,48h and 72h.The samples were analyzed with immunohistochemical methods.The expression of VEGF mRNA was detected by RT-PCR analysis.Results:VEGF protein expression started at 6h.It increased remarkably at 24h,and it was strongest at 48h.VEGF mRNA increased at 6h,while reached peak value at 12h and reduced at 24h,finally returned to normal level at 48-72h.VEGF expression was mainly detected in the periphery of infarcts at every timepoint.Conclusion:These findings demonstrate that the VEGF strong expression can be induced in focal cerebral ischemia reperfusion in vivo.The changes of VEGF levels suggest that VEGF has neuroprotective effect against cerebral ischemic injury.