Experimental Studies On The Different Route Of Transfer RAAV-VEGF₁₆₅ Gene Into Ischemic Rat Brain

ObjectiveTo explore the effect of transfering rAAV-VEGF165 gene into ischemic rat brain by cerebrospinal fluid (CSF) or intravenous route. Observing the expression level of vascular endothelal growth factor (VEGF), the microvascular density in the ischemic penumbra (IP) and the size of infarct. To search a safe and effective gene transfering approach that suitable for clinical status and provide experimental data for the VEGF gene therapy of the ischemic cerebrovascular diseases.MethodsAfter estabilishing a rat s model of permanent middle cerebral artery occlusion (MACO) by nylon suture embolization and cerclage, the rAAV-VEGF165 gene was injected through the cerebellomedullais cisterna or the thigh vein into the ischemic rat brain in 24 hours.On the day 7th and 14th, the rats were killed, infarct size was analysied by TTC staining,VEGF protein and the microvascular density were detected by immunohistochemistry stain in IP.ResultsHigh levels of VEGF protein expression, a significant increase in the number of vessels (p<0.05) and a significant reduction in the ratio of infarct volume (p<0.05) in the gene therapeutic groups were observed when compared with control group and sham-operated group. The effect was more in the CSF's groups than in the intravenous groups.ConclusionThe results indicate the rAAV-VEGF165 gene application by CSF or intravenous route can transfect the ischemic brain tissue and express VEGF protein. The VEGF protein can enhance angiogenesis, increase vessels number, reduce infact volume and protect ischemic brain tissue.