高血压促囊性动脉瘤增大过程中VEGF的作用及其机制的实验研究

The role of VEGF on the growth of hypertensional saccular aneurysm and its mechanism: an experimental study

目的研究VEGF在高血压促囊性动脉瘤增大过程中的作用及其机制。方法SD大鼠24只,以弹性蛋白酶处理右颈外动脉起始部,在1mm处结扎并剪断,建立囊性动脉瘤模型。动物随机均分为高血压组(A组,结扎双侧肾动脉后支升高血压)和对照组(B组)。测量血压变化、动脉瘤的大小。8周时灌注固定取动脉瘤标本,应用免疫组化法评价动脉瘤壁VEGF的表达特点。结果8周时A组血压明显升高(P<0.01),动脉瘤明显大于B组(P<0.01),动脉瘤壁中VEGF表达强度明显高于B组(P<0.01)。结论血压是影响动脉瘤增大的重要因素,VEGF表达上升可能在动脉瘤瘤体扩大中起一定作用。

Objective To study the role of VEGF on the growth of hypertensional saccular aneurysm and its mechanism. Methods Twenty-four SD rots were divided into 2 groups randomly （A and B, each with 12 rats）. Saccular aneurysrns of the carotid artery were reproduced by treatment of initial segment of the external carotid artery （lmrn long） with elastase. In group A, the posterior branches of both renal arteries were ligated in order to produce marked elevation of blood pressure. In Group B hypertension was not produced to serve as the control group. After 8 weeks, the blood pressure and the size of the aneurysrns were measured. Then formalin was infused into the arteries for fixation, and aneurysrns were resected. The expression of vascular endothelial growth factors （VEGF） in aneurysmal wall was assessed with immunohistochemical analysis. Results The size of aneurysms： after 8W, significant difference was found between A and B group （P〈0. 01）. The expression of VEGF in group A was stronger than that in group B. Conclusion The elevation of blood pressure and up-regulation of VEGF expression in aneurysmal wall play important role in growth of the aneurysm.