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

在大鼠离体心标本上，研究了再灌流液中无机离子(Na、Ca、H)的相互作用对缺血后心功能的影响。心脏常温缺血停搏15min，常温再灌流10min，再灌流液中含有不同浓度的无机离子。通过再灌注期主动脉血流量的恢复和肌酸激酶漏出来评价疗效。(1)研究再灌流液中pH的影响。再灌流液的pH值分别为6.8、7.4和7.8。酸性初始再灌流液(pH 6.8)比碱性再灌流液(pH 7.8)具有更好的心肌保护作用。(2)Na和Ca的影响。再灌流液中分别含有Na(25、75或135 mm)和Ca(0.5、1.0或1.5 mm)的不同组合，共9组。Na浓度越高，Ca浓度越低，回收率越高。(3)研究了Na-H和Na-Ca交换抑制剂阿米洛利的影响。再灌流液中含有1.0、10和100微米的阿米洛利。在再灌流液中给药以剂量依赖的方式改善心肌损伤和促进主动脉血流恢复。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.