tPA基因局部定位转染抑制兔动脉损伤后内膜增生的研究  

Study on inhibiting the intimal hyperplasia after rabbit artery injury by local transfection of tissue-type plasminogen activator gene

作　　者：吴忠均[1] 冯虎翼[2] 李德卫[3] 时德[3] 郑树森[1] 

机构地区：[1]浙江大学医学院附属第一医院普通外科,浙江杭州310012 [2]重庆医科大学附属第二医院普通外科,重庆400010 [3]重庆医科大学附属第一医院血管外科,重庆400016

出　　处：《细胞与分子免疫学杂志》2005年第2期213-217,共5页Chinese Journal of Cellular and Molecular Immunology

基　　金：国家重点基础研究发展规划 ( 973 )重点项目资助 (No.2003CB515501);国家自然科学基金资助项目(No. 30270514)

摘　　要：　目的: 观察局部转染组织型纤溶酶原激活物 (tPA)基因, 对手术损伤兔右髂外动脉后内膜增生的影响并探讨可能的机制。方法: 采用显微外科手术方法, 建立兔右髂外动脉损伤模型。将 105只新西兰大白兔随机分为 3组, 每组 35只。A组为生理盐水对照组, B组为脂质体介导的pBudCE4. 1转染组, C组为脂质体介导的pBudCE4. 1 /tPA转染组。用微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 2、3、7、14、28d)再分为 5个亚组, 每个亚组 7只兔。于术后各实验终点, 取损伤段的血管用于病理学检查、电镜观察、RT PCR和免疫组化染色检查。结果: 与A组和B组相比较, 术后各时间点C组血管内膜的厚度、内膜的面积和血管腔的狭窄率均显著减小 (P<0. 01)。术后 28d时, C组血管腔的狭窄率比A组和B组分别降低了 51. 5%和54. 2%。术后各时间点, C组血管壁的tPAmRNA的表达量明显高于A组和B组(P<0. 01), 在术后 7d到达高峰, 并持续到 28d。扫描电镜观察显示, C组的血管壁只见少量血小板附着, 未见血栓形成; 而A组和B组的血管壁可见大量血小板黏附聚集, 且有血栓形成。免疫组化染色显示, C组的血管壁血小板源性生长因子(PDGF)阳性细胞的百分率明显低于A组和B组(P<0. 01)。A组和B组之间相比较, 以上数据差异无显著性(P>AIM: To observe the effects of local transfection of tissue-type plasminogen activator(tPA) gene on intimal hyperplasia of right external iliac artery in rabbits after operation injury, and its possible mechanism. METHODS: Microsurgery injury was used to establish the intimal injury model of right external iliac artery in rabbits. 105 male New zealand rabbits were randomly divided into 3 groups(35 rabbits each group). Group A was normal saline control group, group B was pBudCE4.1-transfected group, and group C was pBudCE4.1/tPA-tansfected group. The normal saline, pBudCE4.1 and pBudCE4.1/tPA transfection solutions were injected into injured vessel walls. Each group was again divided into five subgroups(7 rabbits each subgroup) which were sacrificed at different time (2 d, 3 d, 7 d, 14 d and 28 d after operation). The injured vascular specimens were then harvested for pathologic examination, electron microscope observation, RT-PCR and immunohistochemical staining detection. RESULTS: The intimal thickness and area of vessel walls in group C at every time points after operation were significantly less than those in group A and group B(P<0.01). The stenosis rate of vessels in group C at 28 days after operation decreased by 51.5% and 54.2%, respectively, as compared with groups A and B. The expression of tPA mRNA in group C was significantly higher than that in groups A and B at every time points after operation(P<0.01), reaching the peak at 7 days. The scanning electron microscope examination showed that there were a few thrombocytes adhering to vessel walls in group C but no thrombus, whereas a lot of thrombocytes and thrombi on vessel walls in groups A and B. Immunohistochemical staining exhibited that platelet-derived growth factor(PDGF)-positive cells in the vessels of group C were significantly more than those in group A and B(P<0.01). CONCLUSION: Local transfection of tPA gene can inhibit hyperplasia of neo-intima and prevent restenosis, which is proof of concept for gene therapy of intimal hyperplasia.

关 键 词：TPA 基因 血管损伤 血栓 内膜增生 血管再狭窄 

分 类 号：R973.2[医药卫生—药品]