Expressions and roles of VEGF, VEGFR-1,2 in different cerebral areas of experimental regional ischemic rats

Objective To investigate the expression and role of VEGF and VEGFR 1,2 in the focal cerebral ischemia. Methods The model of middle cerebral artery occlusion was established with the suture occlued method under hypoxia induction.The expression of VEGF and VEGFR 1,2 was observed by immunohistochemistry in SD rats after different times of cerebral ischemia.Results Compared with the contralateral hemisphere,the espression of VEGF and VEGFR 1,2 increased in the penumbra at 6h after MCAO and the highest expression occurred at 24h after MCAO,then decreased gradually to the normal level at 1 week and 2 week respectively.VEGF expressed mainly in neurons,glial cells and vascular endothelial cells in the penumbra and VEGFR 1,2 appeared mainly in vascular endothelial cells of the penumbia. Angiogenesis was seen in the penumbra at 48h after focal cerebral ischemia and reached the highest level at week 1 after ischemia.Conclusion VEGF and VEGFR 1,2 express in neurons,glial cells and vascular endothelial cells at the early stage of focal cerebral ischemia.The expression speeds up the angiogenesis in the penumbra,improves blood provision and helps to recover nerve function.