【摘要】 目的研究球囊扩张术后血管平滑肌细胞(VSMC)中环氧化酶2(COX-2)mRNA表达及选择性COX-2抑制剂处理VSMC后,细胞周期蛋白D1(Cyclin D1)、凋亡蛋白Bcl-2的变化,明确COX-2表达与VSMC增殖凋亡分子机制的相关性。方法用RT-PCR检测20只兔腹主动脉球囊拉伤前后VSMC中COX-2的mRNA表达水平；体外实验将选择性COX-2抑制剂NS-398,作用于兔VSMCs,运用MTF法分别于0,24h,48h,72h检测细胞增殖状态；流式细胞仪观察NS-398对细胞凋亡的影响,进一步采用Western blot检测药物作用前后Cyclin D1、Bcl-2的表达。结果兔腹主动脉球囊拉伤后VSMC COX-2mRNA的表达水平明显高于正常VSMC(P＜0．01),为正常组2．42倍；对照组S及G2/M期DNA百分含量与处理组比值分别为1．31,1．62(P＜0．01),NS-398呈时间、剂量依赖性方式抑制VSMC增殖,促进其凋亡。同时,72h时空白组与NS-398(75μmol/L)处理组Cyclin D1、Bcl- 2表达水平比值分别为2．37和3．81(P＜0．01),故两者表达水平随作用时间延长而下降。结论COX-2在球囊扩张术后血管平滑肌细胞中高表达可能在VSMC过度增殖、凋亡受阻中起重要作用。选择性COX-2抑制剂NS-398可能通过Cyclin D1,Bcl-2影响VSMC的增殖与凋亡,提示COX-2抑制剂可作为预防血管成形术后再狭窄新的候选药物。更多还原

【Abstract】 Objective The purpose of this research was to investigate the COX-2 mRNA level in vascular smooth muscle cell after balloon angioplasty in rabbits and the influence of selective COX-2 inhibitor -NS-398 on proliferation and apoptosis of VSMC,which reveals the potential mechanism of NS-398 effect on VSMC.Methods We assessed COX-2 mRNA in 20 cases of VSMC and adjacent normal tissue by RT- PCR.;Then it was treated with NS-398(a selective COX-2 inhibitor)at different times.MTT assay and flow cytometry were used to measure the proliferation and apoptosis.The expression of Cyclin D1 and Bcl-2 were measured by western blot.Results COX-2 mRNA level were increased in VSMC compared with adjacent normal mucosa(P＜0.05),the median values were 2.42-fold,The ratios of S and G2/M percentage,Cyc- lin D1 and Bcl-2 expression between blank group and NS-398-treated group were 1.31 and 1.62(P＜0.01),2.37 and 3.81(P＜0.01),respectively.NS-398-treated group were inhibited the cells proliferation and induced apoptosis in a dose,time-dependent manner and resulted in significant downregulation of Cyclin D1 and Bcl-2.Conclusions Our results show that overexpression of COX-2 may play a critical role in the development of VSMC after balloon angioplasty.Selective COX-2 inhibitor NS-398 may inhibit the prolifera- tion and induce apoptosis of VSMC through decreasing expression of Cyclin D1 and Bcl-2.It may be a new target of selective COX-2 inhibitor effect on restenosis of Percutaneous Coronary Intervention.更多还原