胰岛素对肾小管细胞缺血再灌注损伤的保护作用

目的：探讨胰岛素对体外肾小管细胞缺血再灌注损伤的保护作用及其机制。方法：建立体外肾小管细胞损伤模型。取肾小管细胞，随机分为3组，分别用正常兔血清（SC组）、再灌注损伤兔血清（SIR组）和再灌注肾损伤兔血清＋胰岛素（IN组）处理培养48h后，分别用分光光度计比色法检测肾小管细胞内超氧化物歧化酶（SOD）、琥珀酸脱氢酶（SDH）活性、钙ATP酶（Ca^2＋-ATPase）活性、一氧化氮（NO）和培养液中丙二醛（MDA）、乳酸脱氢酶（LDH）含量。细胞组化染色检测肾小管细胞内SDH活性。结杲：IN组与SIR组比较，肾小管细胞内SOD、SDH、Ca^2＋-ATPase活性明显升高（P〈0．05）；细胞上清液MDA、LDH、NO含量显著下降（P〈0．05）；细胞组化染色显示IN组SDH颗粒密集，着色较深，而SIR组颗粒稀疏，着色浅淡。结论：胰岛素对损伤肾小管细胞有明显的保护作用，其机制为提高细胞抗氧化能力、减少氧自由基生成并减轻细胞内Ca^2＋超载，促进细胞能量代谢。

Protective effect of insulin on ischemia and reperfusion injury in kidney tubules cells

Objective: To investigate the protective effect of insulin on ischemia and reperfusion injury in kidney tubules cells. Methods: The model of injured kidney tubules cells was established. The kidney tubules cells were randomly divided into three groups, which were cultured with control serum (SC group), reperfusion injury serum (SIR group) and reperfusion injury serum plus insulin (IN group) respectively for 48 hours. And the activities of SOD, SDH, Ca2+-ATPase, NO in kidney tubules cells and the content of MDA, LDH were determined by spectrophotometer. The activities of SDH in kidney tubules cells were detected by cytochemical analysis. Results: Compared with SIR group, the activities of SOD, SDH, Ca2+-ATPase in cells increased significantly and the content of MDA, LDH, NO in cultured medium decreased significantly in IN group(P<0.05). Cytochemical analysis showed that SDH granules were darker and denser in IN group, but lighter and looser in SIR group. Conclusion: Insulin significantly protects kidney tubules cells against IR injury, probably by reducing oxygen free radicals (OFR) production, reinforcing cellular anti-oxidizing competence, and ameliorating energy metabolism.