短暂缺血阈强度运动对冠脉侧支循环生成的作用

关键词：侧支生成  运动  缺血  冠状动脉  心脏康复

Keywords:collateral formation  exercises  ischemia  coronary artery  cardiac rehabilitation

摘要：

      目的：在小型猪可控性心肌缺血动物模型上，观察适宜短暂缺血阈强度运动对缺血区冠脉侧支循环生成的作用。方法：钝缘支装上水囊缩窄器。4周后，冠脉造影证实可控性心肌缺血动物模型建立。随机分为3组：假手术组（SO）、单纯缺血组（PI）、运动组（ET）。PI组通过缩窄器注水加压产生心肌缺血2次/天，每次2min；ET组除以上静息状态心肌缺血外，还需每天平板训练30min，其中包括2次每次2min的缺血阈强度运动。PI及ET组每周训练5d，共8周。SO组不作任何干预。微球测定训练前后缺血区相对心肌血流量（RMBF）；免疫组化Ⅷ染色测定毛细血管密度（CD）；电镜及光镜检查心肌细胞损伤情况。结果：ET组CD显著高于PI组（P<0.01）及SO组（P<0.01）；PI组CD亦显著高于SO组(P<0.01)。RMBF的结果类似于CD。光镜及电镜检查无明显异常。结论：在小型猪可控性心肌缺血动物模型上，适宜短暂缺血阈强度运动可以安全有效地促进冠脉侧支循环生成。

Abstract:

      Objective: To prove that appropriate intermittent exercises at ischemia threshold intension could safely promote coronary collateral formation in ischemic area Method:A balloon obturator was surgically implanted in the first obtuse marginal coronary artery (OM1) of miniature pigs. The subjects were divided into 3 groups: sham-operated (SO), pure ischemia (PI), and exercises training (ET). Subjects in ET group performed individualized treadmill programs for 8 weeks with 2 episodes of exercises-induced ischemia; 2 pre-exercises episodes of pure ischemia induced by brief OM1 occlusion were also conducted. Only pure ischemia was induced in PI group, and SO group remained sedentary for the experimental period. Capillary density（CD） was measured by immunohistochemistry; relative myocardial blood flow（RMBF） by microspheres. Light microscope and electron microscope were also employed to examine whether there was some damage in ischemic area. Result: The CD in the ET group was statistically higher than those in PI and SO groups (P<0.01, P<0.01), the CD in PI group was significantly higher than that in SO group (P<0.01). The results of RMBF were just the same as CD. There was no myocardial damage in ET or PI group by light microscope and electron microscope.Conclusion: Intermittent exercises at ischemia threshold intension could safely promote coronary collateral formation in a porcine model.