大鼠肾缺血再灌注损伤肝内过氧化酶I、过氧化氢酶、细胞外超氧化物歧化酶的表达变化

Expression of peroxiredoxin I,catalases and extracellular SOD in the liver of model rats with renal ischemia-reperfusion injury

摘要目的：观察大鼠。肾缺血再灌注损伤模型肝的功能、形态、氧化应激水平以及抗氧化酶过氧化酶I（PrxI）、过氧化氢酶（CAT）、细胞外超氧化物歧化酶（EC-SOD）的表达变化，探讨肾缺血再灌注损伤对肝的影响及PrxI、CAT、EC-SOD的抗氧化作用。方法：通过无损伤动脉夹钳夹。肾动脉法建立肾缺血再灌注损伤模型。再灌注24h后取血、肝和肾。血清ALT活性采用速率法测定，血清SCr含量采用苦味酸法测定；血清BUN含量采用酶耦联速率法测定。采用H—E染色观察肝、肾的形态学改变。肝组织MDA含量采用硫代巴比妥酸比色法测定；肝组织H2O2含量采用分光光度法测定。抗氧化酶PrxI、CAT、EC-SODmRNA表达水平采用RT-PCR的方法测定，其蛋白水平的表达变化采用免疫印迹测定。结果：肾缺血再灌注损伤组大鼠血清SCr含量、BUN含量和ALT活性均高于对照组；H—E染色结果显示模型组大鼠肾组织、肝组织形态结构均明显受损。肝组织内的MDA含量和Hzoz含量明显高于对照组，PrxI、CAT、EC-SOD的mRNA和蛋白表达水平与对照组相比也明显升高。结论：肾缺血再灌注损伤可导致肝遭受过氧化损伤，形态结构和功能受损，PrxI、CAT、EC-SOD在此过程中可能发挥了抗氧化应激作用，对肝具有保护功能。

Objective： To observe the function, morphology and oxidative stress level of liver and expression change of PrxI, EC-SOD and CAT in model rats with renal isehemia-reperfusion injury（RIRI）, and to explore the effect of renal ischemia- reperfusion injury on the liver and antioxidant function of PrxI, EC-SOD and CAT, Methods： The renal artery of rats was clipped with non-damage vascular clamp to create renal ischemia-reperfusion injury model. The serum, hepatic tissues and kidney tissues were taken after 24 hours of reperfusion. The activities of ALT were detected with rate method. The SCr level in the serum was measured using picric acid method. The BUN level in the serum was measured with enzyme-coupled rate method. The morphological changes of the kidney and the liver were observed under the microscope using H-E staining. The MDA content in the liver was determined with thiobarbituric acid colorimetric method. The H2 02 content in liver was detected with spectrophotometric method. The expression of PrxI, CAT and EC-SOD mRNA in liver was evaluated by RT-PCR and protein level of PrxI, CAT and EC-SOD was estimated by Western blotting. Results： Compared with the control group, the ALT activity, SCr and BUN level in serum of RIRI rats were increased significantly; H-E staining showed that the morphology of the liver and kidney was significantly impaired in the RIRI group. The content of MDA and H2 02 in the liver of RIRI group was higher than that of the control group; the mRNA and protein levels of PrxI, CAT and EC-SOD in liver were also increased significantly. Conclusion： RIRI can lead to peroxide damage of the liver which causes the morphological and functional injury of the liver. The antioxidase PrxI, CAT and EC-SOD may play an important role in inhibiting the oxidative- stress response during the process and protecting the liver.