粘着斑激酶磷酸化与大鼠血管内膜剥脱术后血管新生内膜中细胞增生程度的相关性

摘要

背景:粘着斑激酶磷酸化参与细胞增殖、迁移与凋亡的调节过程.在血管再狭窄发生过程中,粘着斑激酶是否参与、介导了血管平滑肌细胞的迁移与增殖目前尚未见报道.目的:分析粘着斑激酶磷酸化与大鼠血管内膜剥脱术后血管重塑的关系.设计:随机对照动物实验.单位:咸宁学院心血管病研究所、深圳市慢性病防治院和华中科技大学同济医学院附属同济医院心内科.材料:实验于2005-03/05在武汉同济医院心血管实验室完成.选用雄性Wistar大鼠40只,动物实验符合动物伦理学要求.方法:①将40只大鼠按随机数字表法分为5组(n=8),即非内皮剥脱对照组、内皮剥脱术后4 d、8 d、16 d和24 d组.②后4组建立大鼠主动脉内皮剥脱术后再狭窄模型,分别于术后4,8,16和24 d取内膜剥脱部位血管段进行形态学观察,以出现形态学变化作为模型成功的依据;应用Western blolt方法检测粘着斑激酶总含量及磷酸化粘着斑激酶含量.以结扎左颈总动脉的大鼠胸腹主动脉作为对照.主要观察指标:各组大鼠主动脉粘着斑激酶及磷酸化粘着斑激酶表达水平.结果:40只大鼠全部进入结果分析.①非内皮剥脱对照组大鼠主动脉血管可检测到少量粘着斑激酶,主要是以非磷酸化形式存在;内皮剥脱术后4 d组粘着斑激酶和磷酸化粘着斑激酶含量均显著高于非内皮剥脱对照组(P＜0.05).随着损伤时间的延长,粘着斑激酶和磷酸化粘着斑激酶含量显示相同的变化趋势.但粘着斑激酶在术后第8天达到峰值,一直持续到术后第16天,此后开始下降;磷酸化粘着斑激酶峰值出现在术后16 d,在峰值水平上持续时间较短.②形态学观察显示,术后8 d可见新生内膜中局灶性细胞增殖,术后16～24 d内膜呈弥漫性增厚.结论:粘着斑激酶参与大鼠血管内膜剥脱术后血管重塑,血管新生内膜中细胞增生程度与磷酸化粘着斑激酶及粘着斑激酶总含量的变化密切相关.%BACKGROUND: Focal adhesion kinase (FAK) phosphorylation influences the proliferation, migration and apoptosis of cells. However, there are no reports about the role of FAK phosphorylation in migration and proliferation of vascular smooth muscle cells during the process of vascular restenosis.OBJECTIVE : To analyze the correlation between FAK phosphorylation and vascular remodeling after balloon endothelial denudation in rats.DESIGN: Random controlled experiments in animals.SETTING: Cardiology Institute of Xianning College; Shenzhen Center for Chronic Disease Prevention and Control;Department of Cardiology at the Affiliated Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology.MATERrALS: The experiment was carried out in the Laboratory of Cardiology at the Affiliated Tongji Hospital from March to May in 2005. Forty male Wistar rats were used in the study, and they were managed according to the ethical standard of animals.METHODS: ①Forty rats were randomized into five groups (n =8): non-balloon endothelial denudation control group, and 4-day, 8-day, 16-day and 24-day model groups after balloon endothelial denudation. ②The rat models of restenosis following balloon endothelial denudation were built. At days 4, 8, 16 and 24 postoperatively, the denudated vessels were harvested for the detection of the morphological changes, which were taken as the judgment of successful models;Western blot method was used to detect the expression and activity of FAK. Abdominal aorta of left common carotid in rats was served as controls.MAIN OUTCOME MEASURES: The expressions of FAK and phosphorylation FAK in rat artery.RESULTS: Totally 40 rats were all involved in the result analysis.①A small quantity of FAK without phosphorylation could be detected in the controlled rats. Compared with the control group, the expression and activity of FAK in the model group rapidly increased at 4 days after balloon injury (P ＜ 0.05), and they changed in a similar manner with the increase of injury duration. The expression of FAK reached a peak at 8 days and began to descend at 16 days. The expression of phosphorylation FAK reached a peak at 16 days and then rapidly descended. ②Focal hyperplasia of intima was found at 8 days after balloon endothelial denudation, and diffuse hyperplasia of intima was found at 16-24 days after denudation.CONCLUSION: FAK can take part in vascular remodeling after balloon endothelial denudation in rats. The level of intimal hyperplasia is closely associated with the level of FAK and FAK phosphorylation.