早期生长反应因子1特异脱氧核酶对大鼠颈动脉损伤后纤溶酶原激活物抑制剂1表达的影响

Effects of DNA Enzyme Targeting Early Growth Response Factor-1 on The Expression of Plasminogen Activator Inhibitor Type-1 after Balloon Injury of Rat Common Carotid Artery

目的观察早期生长反应因子1(Egr-1)的脱氧核酶(ED5)对大鼠颈动脉损伤后纤溶酶原激活物抑制剂1(PAI-1)水平的影响,初步探讨ED5防治血管内膜增生的机制。方法制备大鼠颈动脉球囊损伤模型,96只大鼠随机分为4组:假手术组、MgCl2组、FuGENE6组和ED5组,每组24只。用微量注射器将各种转染液注入损伤的血管壁,每组按实验终点(术后3、7、14和21天)再分4个亚组,每组6只大鼠。于术后各实验终点,取损伤段血管及血浆样本用于病理学检查、免疫荧光观察、免疫组织化学染色检查、ELISA检测。结果正常动脉早期生长反应因子1表达微弱,动脉损伤后3、7、14至21天,呈持续高表达,经ED5作用后,早期生长反应因子1的表达下降,与同一时间点的MgCl2组和FuGENE6组比较差异有显著性(P<0.01)。与MgCl2组和FuGENE6组比较,术后各时间点ED5组血管管腔狭窄率显著减小(P<0.01)。术后21天时,ED5组血管管腔的狭窄率比MgCl2组和Fu-GENE6组分别降低了58.90%和60.37%。术后各时间点,ED5组PAI-1表达量明显低于MgCl2组和FuGENE6组(P<0.01)。两对照组之间相比较,以上数据差异无显著性(P>0.05)。结论血管内膜损伤后PAI-1表达增加,ED5通过抑制早期生长反应因子1,下调PAI-1的表达,从而减轻血管损伤后早期血栓形成及内膜的增生。

Aim To investigate the effects of DNA enzyme targeting early growth response factor-1（Egr-1） mRNA（ED5） on the expression of PAI-1 after vascular balloon injury and the mechanism of inhibiting neointimal hyperplasia.Methods To establish the intimal injury model of left carotid artery in rats.Ninty-six rats were randomly divided into four groups,sham group,MgCl2 group,FuGENE6 group and ED5 group.Six rats were killed at 3 d,7 d,14 d and 21 d after operation.Vascular sections were stained with heamotoxylin and eosin to identify pathological changes of vascular by light microscope.Immunohistochemistry stain was used to test the expression of Egr-1 inarterial wall.ELISA kit was used to test the expression of PAI-1 gene in plasma.Results The levels of Egr-1 were reduced after treatment with ED5,and there were significant differences between the ED5 group and the MgCl2 and FuGENE6 group（P0.01）.The expression of PAI-1 reduced at every time point in ED5 group（P0.01）.Compared with MgCl2 group and FuGENE6 group,the intimal and media thickness and the stenosis rate of vessel in ED5 group at every time points after operation was significantly lowered（P0.01）.ConclusionThe level of PAI-1 increase after balloon injury.ED5 can through inhibiting the Egr-1,reduce the expression of PAI-1,and then inhibit early thrombosis and neointimal hyperplasia.