血管内^(32)P放射治疗减少血管损伤后内膜增生的实验研究

Study on the interference from radiation to the arterial response of injury

目的 研究血管内放射源照射对损伤血管增生反应的影响。方法 30只常规喂养新西兰大白兔 ,用大于血管直径的球囊过度扩张兔双髂动脉 (球囊 /血管 =1 5 4∶1) ,造成血管壁损伤 ,同时在扩张的球囊中灌注放射性3 2 P进行一侧损伤血管内照射 ,一侧血管单纯扩张作自身对照。按不同照射剂量分成三组 :10Gy、2 0Gy和 40Gy ,每组 10只。在扩张前后进行血管造影 ,4周后再次血管造影同时处死动物取双髂动脉作平滑肌细胞、弹力纤维和胶原纤维染色 ,观察血管受损后放射对血管腔径及其管壁增生的影响。结果 4周后血管造影显示 ,三组兔髂动脉扩张损伤后均发生一定程度的狭窄反应 (P <0 0 0 1)。血管内照射一侧与对照侧比较 ,血管狭窄程度无明显差异 (P >0 0 5 )。病理组织分析 ,10Gy组照射一侧血管内膜增生与对照侧比较无差异 (P >0 0 5 ) ,而 2 0Gy和 40Gy二组照射一侧血管内膜增生较对照侧血管减少 (P <0 0 0 1,P <0 0 4) ,但二组间比较内膜增生减少无差异 (P >0 0 5 )。结论 过度扩张兔髂动脉可产生再狭窄样反应 ,血管内放射在 2 0Gy到 40Gy照射剂量时能减少血管损伤后内膜增生 ,但血管损伤后狭窄程度未受影响。

Objective This study was to evaluate the effects of endovascular irradiation on the proliferation response of injured artery Methods The bilateral iliac arteries of thirty normal fed New Zealand white rabbits were injured by balloon overdilatation (balloon to artery ratio was 1 54∶1) In one iliac artery endovascular irradiation was carried out by a perfusion balloon inflated with 32 P solution The contralateral iliac artery served as an intraanimal control Three doses schedules were studied: 10Gy, 20Gy and 40Gy, 10 rabbits per group Digital angiographic image was made before and after balloon overdilatation as well as at the end of 4 week follow up Subsequently, the iliac arteries injured were excised to be stained with weigert massion for hisopathologic analysis Results The iliac arteries injury of three group rabbits showed certain stenosis at the end of 4 week follow up ( P <0 001) The irradiated arterial diameter did not significantly decreased compared with the control ( P >0 05) Histopathologic analysis of irradiated arteries exhibited the decreased neointimal proliferation compared with the control both in 20Gy and 40Gy high dose radiation groups ( P <0 001, P <0 04). This effect was not observed in 10Gy low dose radiation group But there was not significant difference neointimal proliferation decreasing between arteries treated with the 20Gy or 40Gy ( P >0 05) Conclusion The experimental restenosis like model can be established using overstretch balloon to injure the iliac artery of normal diet rabbit The dose from 20Gy to 40Gy of endovascular irradiation inhibited neointimal proliferation after artery injury The improvement of arterial stenosis was not observed