The study on the interaction of inorganic ions in reperfusion solution on the post-ischemic cardiac performance

在离体大鼠心脏制备中，研究了再灌注中无机离子（Na、Ca、H）对缺血后心脏性能的相互作用。心脏进行15分钟的恒温缺血停搏，然后再灌注10分钟的恒温再灌注，再灌注中含有不同浓度的无机离子。通过再灌注时主动脉血流恢复情况和肌酸激酶渗漏情况来评价疗效。(1)研究了pH对再灌注的影响。再灌注液pH设为6.8、7.4、7.8。酸性初始再灌注（pH 6.8）比碱碱性初始再灌注（pH 7.8）对心肌的保护效果更好。(2)研究了Na和Ca的影响。再灌注液中分别含有不同浓度的Na（25、75、135 mM）和Ca(0.5、1.0、1.5 mM)，共9组。在较高的Na浓度和较低的Ca浓度下，回收率较高。(3)研究了抑制Na- h和Na-Ca交换的抑制剂阿米洛利的作用。再灌注液中分别含有1.0、10和100 μ m的阿米洛利。在再灌注时给药可改善心肌损伤，并以剂量依赖的方式改善主动脉血流恢复。这些数据（1、2和3）与Na-H和/或Na-Ca交换可能参与心肌缺血再灌注损伤机制的假设一致。

Interaction of inorganic ions(Na, Ca, H) in reperfusate on the post-ischemic cardiac performance was studied in the isolated rat heart preparation. Hearts were subjected to 15 min normothermic ischemic arrest followed by 10 min of normothermic reperfusion with the reperfusates containing various concentration of inorganic ions. Effects were evaluated by the recovery of aortic flow and creatine kinase leakage during reperfusion.(1)Effects of pH in the reperfusate were studied. pH in the reperfusate were set in 6.8, 7.4 and 7.8. The acidotic initial reperfusate(pH 6.8) resulted in better myocardial protection than the alkalotic reperfusate(pH 7.8).(2)Effects of Na and Ca were studied. The reperfusates were contained different combination of Na(25, 75 or 135 mM) and Ca(0.5, 1.0 or 1.5 mM), 9 groups in all. The better recoveries were obtained in the higher concentration of Na and the lower concentration of Ca.(3)Effects of amiloride, an inhibitor of Na-H and Na-Ca exchange, were studied. The reperfusates were contained 1.0, 10 and 100 uM of amiloride. Administration of it in the reperfusate ameliorates myocardial damage and improved aortic flow recovery in a dose-dependent manner.These data(1, 2 and 3) are consistent with the hypothesis that Na-H and/or Na-Ca exchange may be involved in the mechanism for ischemia-reperfusion injury in the myocardium.