缺血后处理对大鼠肢体缺血再灌注后肾组织的保护作用

摘要

目的：探讨缺血后处理对大鼠肢体缺血再灌注后肾损伤的影响。方法：依据笔者所在实验室常规方法建立大鼠肢体缺血再灌注(LIR)模型，将30只健康成年雄性 SD 大鼠随机分为三组：对照组(Control 组)、缺血再灌注组(IR 组)和缺血后处理加再灌注组(I-postC 组)，各10例，即橡皮带环绕大鼠双后肢阻断血流4 h，在再灌注前分别给予反复缺血5 min，再灌注5 min，如此重复三次后恢复血流灌注4 h。采用全自动生化分析仪量化出各组动物血浆中肌酐(Cr)、尿素氮(BUN)、C反应蛋白(CRP)变化的趋势；采用分光光度法测定各组动物血浆中超氧化物歧化酶(SOD)、丙二醛(MDA)、黄嘌呤氧化酶(XOD)变化的趋势，及各组动物肾组织中 SOD、MDA、XOD、髓过氧化物酶(MPO)的变化的趋势；HE 染色光镜下观察肾组织的形态学改变。结果：与 Control 组比较，大鼠 LIR 后，血浆及肾组织中 SOD 明显降低；血浆 Cr、BUN、CRP、MDA、XOD 均明显增高，差异有统计学意义(P<0.05或 P<0.01)；肾组织 MDA、XOD、MPO 均明显增高，差异有统计学意义(P<0.05或 P<0.01)；光镜下 HE 染色可见肾小管上皮细胞水肿，有炎细胞浸润。与 IR 组比较，I-postC 组血浆及肾组织中抗氧化酶系统活性增强，各组损伤指标均有减轻趋势。结论：缺血后处理可以减轻肢体缺血再灌注后的肾脏损伤，其机制可能与抑制脂质过氧化反应有关。%Objective:To observe and investigate the protective effects of ischemic postconditioning on the renal function following limb ischemia-reperfusion in rats.Methods:According to my routine laboratory method,the rat limb ischemia reperfusion(LIR) model was established.The 30 healthy male SD rats were randomly assigned to three experimental groups:control group,ischemia-reperfusion(IR) group and ischemic postconditioning(I-postC) group with 10 rats in each group.Ischemia-reperfusion(IR) group means the rats underwent 4 hours ischemia followed by 4 hours reperfusion of hind limbs.Ischemic postconditioning(I-postC) means the rats underwent 4 h ischemia followed by 5 min reperfusion and 5 min ischemia of hind limbs repeated 3 times before 4 h reperfusion.The changing trend of creatinine(Cr),blood urea nitrogen(BUN),C-reactive protein(CRP) in the plasma of different groups were measured by automatic biochemistry analyzer.The changing trend of malondialdehyde(MDA),superoxide dismutase(SOD),xanthine oxidase(XOD) in plasma of different groups and the changing trend of malondialdehyde(MDA),superoxide dismutase(SOD),xanthine oxidase(XOD),myeloperoxidase(MPO) in renal tissue of different groups were measured by spectrophotometry.The histological and ultrastructure changes of renal tissue were observed under lightmicroscope with HE staining.Results:Compared with Control group,the level of SOD in plasma and renal tissue decreased obviously after LIR in rats.The values of MDA,XOD,BUN,Cr,CRP in plasma increased remarkably were significant differences(P<0.05 or P<0.01) and the trend of indexs such as MDA,XOD and SOD in the renal tissue were similar to that of in plasma(P<0.05 or P<0.01).Under the light microscope,dropsy can be seen in renal tubular epithelial cells and infiltrated with inflammatory cells with HE staining.Antioxidant system in plasma and renal tissue of I-postC group was enhanced more than that of IR group.The index of injury were not serious in I-postC group than that in IR group.Conclusion:Ischemic postconditioning can reduce limb ischemia reperfusion renal injury,The cause may be associated with inhibiting lipid peroxidation reaction.