低流量预适应心肌保护的实验研究

Experilmental study of effect of low flow preconditioning on heart preservation

目的 :探讨低流量预适应对缺血心肌的保护作用。方法 :采用离体大鼠工作心模型 ,大鼠共 32只 ,随机分成两组。实验以低流量缺血预适应结合冷晶体停搏 ,行心肌保护研究 (预适应组 ) ,并与单纯冷晶体停搏、低温保存之心肌 (对照组 )进行对比研究。每组中各半数 (8只 )在缺血末测心肌 ATP含量。结果 :预适应组心肌缺血后心功能的恢复、ATP的含量均明显高于对照组 ,且心肌超微结构损害较轻 ,心肌酶释放明显减少。结论

Objective:To evaluate the protective effects of low flow preconditioning before hypothermic cardioplegic arrest on isolated rat working heart subjected to 120 minutes of ischemia.Method:The isolated rat working heart models (n=32),which were randomly divided into 2 groups,were used in this study.The cardiac arrest was induced with St.Thomas Ⅱ solution after low flow preconditioning in group Ⅰ;In group Ⅱ,the cardiac arrest was induced only with St.Thomas Ⅱ solution without preconditioning.In 8 of each group,myocardial ATP content was determined at the end of ischemia.Result:In group Ⅰ,recovery of heart function was better than group 2.The myocardial ATP content was higher and microstructure damage was lesser in group 1.The myocardial enzyme release also was smaller in group 1.Conclusion:Low flow ischemic preconditioning prior to cardioplegic arrest enhances myocardial function recovery after prolonged cardioplegic arrest,preserves more ATP and reduces release of LDH.