局部应用VEGF-165抑制兔颈移植静脉内膜增生的研究

Local application of slow-releasing membrane carrying VEGF-165 inhibits neointima hyperplasia in rabbit vein graft

关键词:  动脉旁路移植术  移植静脉  VEGF-165  内膜增厚

Key words:  coronary artery bypass grafting  vein graft  VEGF-165  intimal hyperplasia

摘要:

目的 探讨局部应用VEGF-165抑制兔颈移植静脉内膜增生的机制。方法 健康家兔24只,均建立颈外静脉-颈总动脉移植模型并分为对照组及实验组。对照组移植静脉周围仅应用Pluronic-F-127,实验组移植静脉周围应用Pluronic-F-127+VEGF-165。观察静脉移植血管外膜、内膜增生情况,移植静脉VEGF及eNOS的表达量,增殖细胞核抗原PCNA表达情况。分析外膜厚度与静脉桥血管内膜增生的关系。结果 与对照组相比,实验组移植静脉内膜增厚明显减轻、而外膜明显增厚,移植静脉eNOS的表达量明显增加；实验组移植静脉平滑肌细胞向外膜方向迁移；术后免疫组化检查显示,实验组移植静脉血管壁内膜VEGF-165的蛋白含量高；两组移植静脉PCNA的表达量未及明显差异。结论 VEGF-165可以通过增加内皮eNOS表达加速移植静脉血管内皮化,促进移植静脉外膜生长促进平滑肌向外膜迁移减轻移植静脉内膜增厚。

Abstract:

Objective To investigate the effects of local application of VEGF-165 on jugular vein graft in rabbit and its mechanism. Methods Twenty four New Zealand white rabbits were divided into two groups: pluronic F-127 without VEGF-165 was locally applied on the jugular vein graft in control group; and pluronic F-127+VEGF-165 was applied in experimental group. The degree of adventitia and intimal hyperplasia in vein graft were assessed. The expression of VEGF was detected by immunohistochemistry; the expression of eNOS and PCNA was detected by Western Blot. The relationship of the thickness of vein graft adventitia and the degree of intimal hyperplasia was analyzed. Results Compared with control group, the intima hyperplasia was less; the adventitia hyperplasia was greater in experimental group; more SMC moved outwards in experimental group. The western blot test showed that there was no significant difference in the expression of PCNA between two groups; the expression of intimal VEGF and eNOS in experimental group was significantly higher than that in control groups. Conclusion VEGF-165 can increase the activity of eNOS in vein intima and accelerate the endothelialization. VEGF-165 can promote the growth of vein adventitia and attract the smooth muscle cell moving towards outside which contributes to alleviating the intimal hyperplasia.