内皮祖细胞捕获支架防治犬肝静脉再狭窄的实验研究

Prevention of restenosis by automatic catching EPCs in hepatic venous stents

目的观察内皮祖细胞(Endothelialprogenitorcells,EPCs)捕获支架置入预防犬肝静脉支架内再狭窄的效果。方法家犬24只,按随机数字表法分为实验组与对照组,每组12只,每组再分为2个亚组各6只。实验组置入EPCs捕获支架,对照组直接置入支架。术后第1周每组处死一个亚组动物,取部分支架内组织用于扫描电子显微镜观察。术后第8周行肝静脉造影复查,处死剩余动物,然后取支架内及邻近支架肝静脉血管组织织用于光学显微镜观察。结果术后第1周,通扫描电子显微镜观察支架腔面内皮化程度实验组明显优于对照组。术后第8周肝静脉造影复查,实验组支架开放情况明显优于对照组(t=20,P<0.01);光学显微镜观察实验组平均新生内膜厚度、平均新生内膜面积、平均百分狭窄面积均显著优于对照组(t值分别为6.08、4.50和5.52,P<0.01)。结论 EPCs捕获支架可以促进肝静脉支架腔面的血管内皮生长,预防再狭窄。

Objective To investigate the effect in preventing restenosis of hepatic venous stents by automatic catching EPCs in dogs.Methods Twenty-four dogs were divided into test group and control group randomly（12 dogs in each group）.Each group was divided into 2 subgroup（6 dogs in each subgroup）.The CD34 coated metallic stents were placed into hepatic veins in test group and bare metallic stents were placed in control group.Parts of the intra-stent vascular tissues were studied by means of scanning electron microscopy.The dogs were followed up for 8 weeks underwent hepatic venography before they were killed to assess the patent extent of stents.The vascular tissues near the stents were used for observation under the optical microscope.Results At the first week after stent placement,it was proved that test group was superior to control group clearly in the endotheliosis by scanning electron microscopy.At the eighth week,hepatic venography showed that the patency ofstents in test group was also superior to that in control group（t =20,P〈0.01）,and light microscope demonstrated that mean neiontime thickness,mean neiontime area,and mean percentage area of narrowing in test group was significantly less than that in control group,respectively（t=6.08,4.50,5.52,respectively,P〈0.01）.Conclusion The automatic cahting EPCs can accelerate the endothelization covered stents in hepatic veins and prevent the formation of restenosis.