自体静脉移植术后血管平滑肌细胞凋亡与增殖的研究

目的检测静脉移植术后不同时期血管平滑肌细胞(VSMCSs)增殖与凋亡,进一步探讨其在血管内膜增生(IH)发生中的作用.方法60只Wistar大鼠建立自体静脉移植模型,自身正常静脉做对照,应用DNA原位缺口末端标记技术(TUNEL)及免疫组织化学方法检测不同时期(术后1、2、4、6、8周)凋亡及Ki-67表达情况,并作相关分析.结果术后1～8周,移植静脉VSMCS的TUNEL及Ki-67的阳性表达均显著高于对照组(P＜0.01).术后1、2周,二者表达均达高峰,且TUNEL表达低于Ki-67表达;而术后4～8周,TUNEL表达高于Ki-67表达.二者的表达具有显著相关性(r=0.813,P＜0.05).结论静脉移植术后VSMCSs的增殖与凋亡共存,且具有明显相关性,提示二者均参与静脉的重塑过程;术后移植静脉的再狭窄可能与VSMCS的凋亡和增殖失衡有关;对再狭窄的防治应采用调节VSMCS增殖和凋亡平衡的联合策略.

Apoptosis and proliferation in smooth muscle cells of autogenous vein graft in rat experimental model

To detect the functions of proliferation and apoptosis in the intimal hyperplasia of autogenous grafted veins through investigating vascular smooth muscle cells (VSMCS) in different phases after transplantation. Autogenous vein graft model was established in 60 Wistar rats. The grafted veins were harvested from 1st to 8th weeks respectively after transplantation. The level of apoptosis and the expression of Ki-67 were detected by means of TUNEL technique and immunohistochemical stain respectively in different stages after grafting. The autogenous normal vein served as auto-control. From 1st to 8th weeks after operation, the expressions of both TUNEL and Ki-67 were significantly higher than those of control groups (P <0.01). Both TUNEL and Ki-67 showed peak expression value in the first tow weeks, and the percentage of positive cells of TUNEL was lower than that of Ki-67. But a reversed result was shown from 4th to 8th weeks. The expressions of TUNEL and Ki-67 were significantly correlative (r =0.813, P <0.05). Conclusions] After autogenous vein graft, both proliferation and apoptosis of VSMCSs coexisted and had a significant correlation, which indicated that the two processes participated in vascular remodeling. The unbalance of proliferation and apoptosis may relate to the stenosis of the vein graft, and regulating the balance of them may be useful to prevent restenosis.