急性心肌缺血再灌注时中性粒细胞胞浆游离钙和氧自由基的变化

The Changes of Cytoplasmic Free Calcium and Oxygen Free Radical of PMN after Acute Myocardial Ischemic Reperfusion

本研究旨在观测急性心肌缺血，再灌注时外周血中性粒细胞（ＰＭＮ）胞浆游离钙［Ｃａ２＋］ｉ、氧自由基的变化规律及与心肌钙、氧自由基的关系，以评定外周血指标对心肌缺血再灌注损伤（ＭＩＲＩ）的诊断价值。用家兔３０只，随机分为缺血前、缺血３０分钟、再灌注３０、９０、３６０分钟５组，取外周血ＰＭＮ和心肌测定丙二醛（ＭＤＡ），超氧化物歧化酶（ＳＯＤ）及ＰＭＮ［Ｃａ２＋］ｉ和心肌组织钙。结果示缺血３０分钟外周血ＰＭＮ［Ｃａ２＋］ｉ、ＭＤＡ较缺血前明显升高，而ＳＯＤ活性则明显下降，至再灌注期上述变化更显著（Ｐ均＜０．０１）。且其变化规律与心肌钙、ＭＤＡ和ＳＯＤ的改变是一致的；二者间呈显著正相关（Ｐ＜０．０５～０．０１）。结论为自由基与钙超负荷共同参与了ＭＩＲＩ，外周血ＰＭＮ的检测可作为判断ＭＩＲＩ的可靠方法。

The changes of cytoplasmic free calcium[Ca￣(2+)]i,malondialdehyde(MDA) and superoxides dismutase(SOD)of polymorphonuclear leukocytes (PMN)in peripheral blood and myocardium were observed after acute myocardial ischemic and reperfusion. The relationship between them and myocardial Ca￣(2+),MDA and SOD were also analyzed to find out whether the changes of the aforementioned parameters in the peripheral blood could be used to define the myocardial ischemic reperfusion injuries.After 30 minute occlusion of the rabbit coronary artery and reperfusion for 30, 90, 360 minutes ,the contents of [Ca￣(2+)]i、MDA and SOD of PMN and myocardial Ca￣(2+),MDA and SOD were measured. The PMN [Ca￣(2+)], and MDA were increased and SOD decreased after myocardial ischemia.These changes were more marked after reperfusion (P<0.01). A close correlation between [Ca￣(2 +)]i, MDA, SOD of PMN and Ca￣(2+),MDA,SOD of myocardium were observed (P<0. 05～0.01). The results suggest that the myocardial ischemic reperfusion injury might be induced by Ca2+ overload and oxygen free radical.The levels of [Ca￣(2+)] , MDA and SOD of PMN may be used as indicators for evaluating myocardial ischemic reperfusion injury.