凝血酶调节蛋白基因防治血管内膜增生狭窄的实验研究

目的:观察凝血酶调节蛋白(Thrombomodulin,TM)基因转染兔髂动脉损伤模型后,对动脉血管内膜增生狭窄的防治作用。方法:用注射式加压转染的方式对兔动脉壁转染pcDNA3.1/hTM质粒,再制造动脉损伤-阻滞模型,于术后3天、7天、14天、28天用免疫组化的方法观察TM蛋白在各组血管腔内的表达,术后14天、28天用彩色多普勒观察活体吻合口内径和血流流速;再做病理切片Verhoeff染色,观察血管内膜增生的程度、部位,计算血管内膜面积、中膜面积和血管狭窄率。结果:术后3天、7天、14天、28天hTM质粒转染组中hTM表达一直保持在高水平,7天达到高峰,14天、28天虽有所下降但是表达强度仍然高于载体质粒转染组合空白对照组。在术后14天、28天彩色多普勒观察测量吻合口内径:hTM质粒转染组分别为1.93mm±0.34mm,1.89mm±0.28mm;载体质粒转染组为1.59mm±0.43mm,1.38mm±0.28mm;空白对照组1.46mm±0.25mm,1.44mm±0.32mm。在这两个时间点,hTM质粒转染组血管狭窄率为32±23%,37±14%;载体质粒转染组为58±21%,63±17%;空白对照组为58±19%,61±23%。结论:hTM基因在转染动脉壁后能减少动脉损伤-阻滞模型在后期的血管内膜增生,改善血管的狭窄状况。

The Experimental Study of Preventive Effects from hTM Gene for Neointima Formation and Stenosis in Rabbit Artery Injury-block Model

Objective: To observe neointima formation in rabbit artery injury-block model which were transferred by pcDNA3.1/hTM plasmids. Methods: After transferred pcDNA3.1/hTM plasmid into rabbit artery by high-pressure injection, rabbit common iliac artery were cut and anastomosed again. The expression of hTM protein at vessels wall were examined with immunohistochemistry at 3d,7d,14d and 28d after operation. At the 14d and 28d after second operation, the inside diameter of anastomotic stoma and blood flow velocity were checked by color Doppler. The treated artery were sliced and stained by Verhoeff. Local neointima formation and the ratio stenosis of intervascular was calculated by computer. Result: The expression of hTM was at higher level in hTM gene treated group than vector treated group and control group at 3day, 7day, 14day, 28day after second operation. At 7day, the level was highest. At 14day and 28day, Color Doppler showed that the stoma bore were 1.93mm±0.34mm(14d),1.89mm±0.28mm(28d) in hTM gene treated group；1.59mm±0.43mm(14d),1.38mm±0.28mm(28d) in vector treated group；1.46mm0.25mm,1.44mm±0.32mm in control group. The ratio stoensis were 32%±23%(14d),37%±14%（28d） in hTM gene treated group；58%±21%(14d),63%±17% in vector treated group；58%±19%(14d),61%±23%(28d) in the control group，respectively. Conclusion: Human thrombmodulin gene could reduce the neointima formation and vascular stoensis in rabbit artery injury-block model.