实验性血管外膜去除后高血压对血管内膜增殖和血管反应性的影响

Effect of Hypertension on Intima Proliferation and Vasoconstriction After Adventitia Removal

本文观察外膜去除后升高血压对血管结构及功能的影响。实验采用在体去除兔颈动脉外膜方法 ,术后分对照组及高血压组 (植入微型药物渗透泵恒量注入去甲肾上腺素 ) ,分别于术后 1周及 2周后取出颈动脉。用图像分析系统测定内膜及中膜面积 ;应用多道生理仪测血管反应性 ;RT PCR检测mRNA表达。结果 1)外膜去除后血管内膜增生 ,术后 2周高血压组去外膜侧内膜面积 /中膜面积较对照组增高 (P <0 0 5 ) ;2 )与完整侧比较 ,术后 1周对照组去外膜侧血管对去甲肾上腺素 (NE)的收缩反应减弱 (P <0 0 5 ) ;而术后 2周对照组与高血压组反应均增强 (P <0 0 5 )。与对照组比较 ,术后 1周及 2周高血压组去外膜侧血管环反应增强 (P <0 0 5 )。 3)与对照组比较 ,术后 2周高血压组去外膜侧Rho AmRNA表达及MCP 1表达较对照组增高 (P <0 0 5 )。术后 2周对照组及高血压组去外膜侧Rho Ki nasemRNA表达较完整侧上调 (P <0 0 5 ) ;术后 1周高血压组完整侧及去外膜侧Rho KinasemRNA表达较对照组上调 (P <0 0 5 ) ,2周时上调更明显 (P <0 0 1)。术后 2周高血压组去外膜侧MCP 1mRNA表达较完整侧上调 (P <0 0 5 ) ;术后 2周高血压组完整侧及去外膜侧MCP 1mRNA表达明显上调 (P <0 0 1)。结论 高血压可加剧外膜去除后的血?

Objective To study the effect of hypertension on vascular structural and functional changes after removal of adventitia. Methods Rabbits( n =38), whose carotid artery adventitia was removed were randomly allocated into control group 1(as control) and group 2(norepinephrine was infused with osmotic minipumps). Seven days and 14 days after the operation, the intima and media were measured by image analyse system, vasotension changes were measured using a force transducer connected with a polygraph.\ mRNA expression were measured by RT-PCR. Results 1)The adventitia removal induced hyperplasia of intima which was most remaskable at day 14 in group 2( P <0.05). 2)Compared with intact vessel ring, norepinephrine (NE)-induced contraction of adventitia denuded vessel ring was less in group 1 at day 7, greater at day 14( P <0.05 or P <0.01). 3) 14 days after operation, the expression of Rho-Kinase mRNA were increased in group 1( P <0.05)and in group 2( P <0.01).\ The expression of MCP-1 mRNA were increased in group 2(\%P\%<0.01). Conclusions Hypertension enhanced the neointima formation and hyperreactivity of vascular vessels after removal of adventia. The mechanism of which may be ascnibed to activating of Rho-Kinase and MCP-1 in the vascular vessel wall.