针对Egr-1mRNA的10-23脱氧核酶抑制大鼠动脉损伤后内膜增生的研究

Study on inhibiting intimal hyperplasia after vascular balloon injury in rats by 10-23 DNA enzyme targeting Egr-1mRNA

目的探讨针对Egr-1mRNA的10-23脱氧核酶对大鼠动脉损伤后内膜增生的影响和可能的机制。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,A组为假手术组;B组为1mmol/LMgCl2对照组;C组为FuGENE6对照组;D组为FuGENE6介导的ED5转染组;每组再按术后3,7,14和21d,分为4个亚组,每组6只。术后3、7、14、21d各处死每组动物6只,分别应用RT-PCR和Western-blot技术检测血管组织Egr-1mRNA水平及蛋白合成情况;HE染色观察损伤血管内膜的增生情况;免疫组织化学染色观察PCNA的表达。结果与B组和C组比较,D组各时间点血管内膜、中膜的厚度和管腔的狭窄率均显著减小(P<0.01);正常血管组织有微量Egr-1表达,术后Egr-1mRNA和蛋白水平逐渐增高,而D组血管组织E-gr-1mRNA和蛋白水平较B组和C组均降低(P<0.01);免疫组织化学染色显示,术后3dPCNA表达开始增加,7d达高峰,14d开始下降,D组血管壁PCNA阳性细胞百分比明显低于B组和C组(P<0.01)。B组和C组之间相比较,以上各指标差异均无显著性(P>0.05)。结论ED5可能通过抑制Egr-1和PCNA的表达,而减轻血管损伤后内膜增生。

[Objective] To investigate the effects of DNA enzyme targeting Egr-1mRNA （EDS） on intimal hyperplasia after vascular balloon injury and to primarily study its mechanism of inhibiting neointimal hyperplasia. [Methods] To establish the intimal injury model of left carotid artery in rats. Ninety-six rats were randomly divided into four groups, group A was sham-group; group B was MgCl2-eontrol group; group C was FuGENE6-eontrol group; group D was EDS-transfected group. MgCl2, FuGENE6 and ED5 was delivered the artery wall by the end of 2F balloon catheter. Six rats were killed at 3 d, 7 d, 14 d, 21 d after operation. Vascular sections stained with heamotoxylin and eosin to identify pathological changes of vascular by light microscope. Immunohistochemical staining for PCNA was performed. RT-PCR, western-blot methods were used to assay the changes of Egr-lmRNA expression and Egr-1 protein expression. [Results] Compared with group B and C, the intimal and media thickness and the stenosis rate of vessel in group D at every time points after operation was significantly less （P 〈0.01）. There is less expression of Egr-1 in normal vascular wall. The expression of Egr-1 was up-regulated after operation. Com-pared with group B and C, the level of Egr-1 mRNA expression and Egr-1 protein in group D lowered in every time points（P 〈0.01 ）, immunohistoehemieal staining exhibited PCNA-positive cells in group B and C were significantly more than those in group D （P 〈0.01）. [Conclusion] ED5 can inhibit intimal hyperplasia after artery injury by decreasing the expression of Egr-1 and PCNA.