实验性血管成形术后狭窄变化的动态观察

Dynamic Observation of Vascular Constrictive Changes after Balloon Angioplasty: An Experimental Study in Rats

目的 建立球囊成形术后动脉狭窄的简易动物模型 ,观察成形术后血管壁各部分变化在动脉狭窄发生中的作用。材料与方法 用 2FFogarty球囊导管损伤大鼠左颈动脉 ,分别在 8周内不同时间点获取标本 ,利用光镜和电镜研究动脉球囊损伤后的形态变化 ,另选取 2周组和 1个月组动物于造模前、造模后进行DSA和MRI检查。结果 (1)光镜与电镜表现 :损伤后内皮细胞剥脱 ,血小板及单核细胞附着 ,中膜平滑肌细胞坏死和增殖 ,平滑肌细胞由收缩表型转变为合成表型以及随后的内膜平滑肌细胞出现与复制 ,弹力纤维、胶原和蛋白成分等细胞外基质的堆积导致内膜明显增厚 ,管腔狭窄。 (2 )影像学表现 :DSA及MRI均清楚反映出造模后的模型动脉狭窄变化。结论 大鼠球囊损伤模型能较好地反映球囊损伤后血管的病理变化过程且经济、简便易行 ,应是初筛研究的首选模型 ;DSA、MRI是监测模型血管动态变化的较好方法。

Objective To establish a simple animal model of arterial stenosis following angioplasty, to observe the arterial wall's change and its significance in the development of vascular stenosis.Materials and Methods The left carotid arteries of 36 rats were injured with a 2F Fogarty balloon catheter. The injured carotid arteries were dissected at different point of time during the study period of 8 weeks. The pathologic and morphologic changes of the injured arteries were observed under both light and electronic microscope. Besides, DSA and MRI were performed 2 weeks and one month after the procedure to observe the vascular changes.Results (1) Microscopic findings after balloon injury: endothelial denudation, adherence of platelets and monocytes, necrosis and proliferation of medial smooth muscle cells, transformation of smooth muscle cells from contractile to synthetic phenotype with subsequent formation and duplication of the intimal smooth muscle cell, extracellular matrix accumulation, etc. All the above changes lead to severe intimal hyperplasia and vascular stenosis. (2) Imaging findings: both DSA and MRI well displayed the constrictive changes of the ballon injured arteries.Conclusion It is indicated that this simple and economical rat model can well reflect the complicated morphological changes of the artery after injury, and this model should be considered as the first choice for preliminary study. DSA and MRI are ideal imaging means for dynamically observing the vascular changes.