在急性局灶性脑缺血早期VEGF、FLT-1、FLK-1 mRNA的表达及作用研究

目的 检测血管内皮生长因子（VEGF）及其受体（FLT-1，FLK-1）mRNA在急性局灶性脑缺血中的表达，并探讨血管内皮生长因子在急性局灶性脑缺血中的作用。方法 建立SD大鼠永久大脑中动脉闭塞（MCAO）模型。应用原位杂交技术检测血管内皮生长因子及其受体基因在局灶性脑缺血后不同时间点的表达。结果 原位杂交显示VEGF及FLT-1，FLK-1mRNA在局灶性脑缺血后3h即开始表达增强。VEGFmRNA和FLT-1，FLK-1mRNA于48h达高峰，后VEGFmRNA逐渐下降。至14d恢复到对照水平。而FLT-1，FLK-1mRNA在达高峰后，下降更加缓慢，约在21d时达对照水平，VEGFmRNA主要在缺血半影区神经元表达，同时在胶质细胞和血管内皮细胞表达，而FLT-1，FLK-1mRNA主要在缺血周边血管内皮细胞表达，但也在神经元表达。在缺血后48h半影区周边出现血管增生。并逐渐向中心区延伸，于缺血后7d达高峰，整个半影区可见明显敌国管增生。结论 急性半影区周边出现血管增生，并逐渐向中心区延伸，于缺血后7d达高峰，整个半影区可见明显血管增生。结论 急性局灶性脑缺血早期VEGFmRNA及FLT-1，FLK-1mRNA在神经细胞。胶质细胞，血管内皮细胞均有表达，可促进缺血半影区的血管增生。对改善急性局灶性脑缺血早期缺血半影区血供有重要作用。

The study on expression and role of vascular endothelial growth factor and its receptor gene in acute focal cerebral ischemia at early stage

Objective To study the expression of VEGF mRNA and FLT 1,FLK 1 mRNA in the acute focal cerebral ischemia at early stage,anf to explor the function of VEGF in the acute focal ischemia. Methods The gene expression of VEGF and FLT 1,FLK 1 in acute focal ischemic tissue of different times after MCAO was assayed by in situ hybridization (ISH). The angiogenesis was observed to explore the correlation of VEGF and FLT 1,FLK 1. Results The results of ISH revealed that the gene expression of VEGF and FLT 1,FLK 1 increased from 3h after the MCAO. The expression of VEGF gene reached its peak at the time of 48h after ischemia,then declined gradually,became normal after about 14d. While the gene of FLT 1,FLK 1 declined more slowly after reaching the peak,returned to the control level at the time of 21d. The increasing expression of VEGF mRNA located mainly in the neurons,neuroglia and vascular endothelial cells of penumbra,while FLT 1,FLK 1 mRNA expressed increasingly mainly in the vascular endothelial cell of peripheral ischemic region,it also expressed in the neurons. The angiogenesis appeared in the peripheral ischemic region from 48h after the ischemia,most evidently at the time of 7d. Conclusion VEGF mRNA and FLT 1,FLK 1 mRNA express in the neuron,neuroglia,and vascular endothelial cell. Their expression promotes the angiogenesis in the penumbra and improves the blood supply.