肾缺血再灌注细胞内钙水平与氧化应激损伤研究

目的 观察肾细胞中游离钙(Ca~(2+)]i)及氧自由基在缺血再灌注损伤过程中的改变情况,探讨二者在再灌注肾损伤中发生作用机制。方法 摘除Wistar大鼠左肾,钳夹右侧肾蒂,建立急性缺血再灌注肾损伤模型,应用Fura-2/AM荧光指示剂测定缺血再灌注大鼠肾细胞内Ca~(2+)]i浓度的变化,同时测定谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果 缺血再灌注不同时期肾细胞内Ca~(2+)]i浓度均有不同程度增高,与对照组相比差异有显著意义,各实验组SOD活力水平降低,与对照组相比差异有显著意义,MDA生成高于对照组,GSH-Px在再灌注早期活力减弱,明显低于对照组,晚期活力基本恢复。结论 1.缺血再灌注不同时期大鼠肾细胞内Ca~(2+)]i超载和不同程度的氧化侵袭,在缺血再灌注肾损伤病理过程中起重要作用;2.再灌注时间与肾细胞内Ca~(2+)]i超载呈正相关,提示再灌注损伤通过不同机制加重细胞钙超载。

Study of Intracellular Ionized Calcium Level and Oxidative Stress during Renal Ischemic Reperfusion Injury

Objective To study and explore the effect and mechanism of intracellular inonized calcium level and oxidative stress on renal injury during renal isehemic reperfusion process. Methods The model of rat's acute renal isehemic reperfusion injury was established, Renal intracellular Ca2+ ]i level of it was determined by Fura-2/AM fluorescence assay, and glutatliiorie peroxidase (GSH-Px) as well as superoxide dis-mutase (SOD)activity and malonic aldehyde (MDA) were raeasured.Results Compared with control group, renal intracellular Ca + ]i level increased significantely at different period of isehemic reperfusion, SOD activity reduced prominantly;GSH-Px activity reduce at earlier period,but recovery in late period. MDA content increased significantely . Conclusion First, at different period of rat s acute renal isehemic reperfusion injury, renal intracellular Ca2 + ] i overloading and die degree of oxidative invasiveness may have an importance role in pathology of renal injury. Secondary, there is positive relationship between reperfusion time and renal intracellular Ca2+ ]i overloading, it is suggested that the reperfusion injury might aggregate overload of intracellular Ca2+ ]i by different mechanisms.