家兔颈动脉内支架置入后细胞凋亡的动态观察

Serial studies of apoptotic smooth muscle cells in rabbit carotid artery after stenting

目的 观察兔颈动脉内支架置入后细胞凋亡的动态变化 ,探讨细胞凋亡在再狭窄形成中的作用。方法 采用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法 (TUNEL)及透射电镜 ,检测兔颈动脉内支架置入后 7、1 4、30、90d的细胞凋亡。结果 支架术后 7、1 4d未观察到平滑肌细胞凋亡 ,术后 30d在新生内膜中观察到明显的细胞凋亡 ,90d时单位面积内凋亡细胞数显著高于 30d〔(4 .5 0± 1 .2 9)vs (1 3.5 0± 1 .91 )个 /0 .1mm2 ,P <0 .0 0 1〕。透射电镜下凋亡细胞表现为胞浆浓缩 ,染色质浓缩成团 ,边聚于核膜形成新月体。结论 细胞凋亡是支架置入后再狭窄形成中一个重要的病理学特征 ,在后期明显增多 ,调节着新生内膜中平滑肌细胞的数量。

ObjectiveTo investigate the occurrence and ex tent of apoptosis in restenosis after stenting.MethodsPlat iniumIridium alloy stents were implanted into the rabbit right carotid arterie s.Samples were retrieved on day of 7?th,14?th,30?th and 90?th after stenting .Apoptot ic smooth cells were detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL) and transmission electron microscopy(TEM).ResultsOn 7?th and 14?th d after stenting, there were no det ectable apoptotic cells. The apoptotic cells appeared in the neointima 30?th an d 90?th d after stenting, and the number of apoptotic cells in 30 d were less tha n that in 90?d [~{*)~}4.50~{**!@~}1.29,13.50~{!@~}1.91(the apoptotic cell number per 0.1m m~{*,~}2 ),~{*+~}P~{*+~}<0.001].TEM illustrated ultrastructural features of apoptotic SMC :nucle ar and cytoplasm condensation, and the condensed chromatin formed crescents. ConclusionCell apoptosis is a feature of restenotic patholo gy af ter stenting, and its number increase in late course mentioned above. It can reg ulate the number of smooth muscle cells.~{!<~}HQ~{!=*$~}