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目的:通过建立大鼠心死亡供肾常温机械灌注(normothermic mechanical perfusion，NMP)模型，探讨空气氧合NMP和氧气氧合NMP对心死亡供肾损伤修复的影响。方法:取12只12~14周龄的健康雄性SD大鼠，建立大鼠心脏死亡供体器官捐献(donation after cardiac death，DCD)模型。大鼠肾脏在热缺血损伤30 min并冷保存8 h后，采用随机数字表法随机分为使用氧气氧合NMP(O组，6只)、空气氧合NMP(A组，6只)2 h。另取相同数量大鼠，采用随机数字表法随机平分为开腹即获取肾组织的假手术组(C组，6只)和心死亡后仅静态冷保存8 h的心死亡肾脏静态保存组(SCS组，6只)作为O组和A组的对照。微板法检测肾灌注液损伤指标肌酐(Cr)、天冬氨酸氨基转移酶(AST)和乳酸脱氢酶(LDH)水平变化，HE染色评定肾组织中肾损伤指标，免疫组织化学和蛋白质印迹法检测髓过氧化物酶(MPO)、细胞间黏附分子-1(ICAM-1)表达，酶联免疫吸附法检测TNF-α和IL-6水平，硫代巴比妥酸和WST-8法测定脂质过氧化产物丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性。采用n t检验和单因素方差分析比较组间变量的差异。n 结果:氧气氧合NMP体系(O组)的肾动脉处灌注液氧分压为(576.3±68.2)mmHg，空气氧合NMP体系(A组)氧分压为(137.0±39.1)mmHg，组间比较，差异有统计学意义(n P<0.05)。HE染色结果显示，SCS组、O组和A组的病理损伤评分分别为(7.0±0.1)分、(5.0±0.9)分和(2.5±0.5)分，SCS组肾损伤评分显著高于后两组，组间差异均有统计学意义(P均<0.05)；A组评分亦较O组显著降低，差异亦有统计学意义(n P<0.05)。O组供肾NMP前后灌注液的△Cr、△AST、△LDH分别为(43.9±52.8)μmol/L、(532.3±52.8)U/L和(9998.0±2014.4)U/L，A组上述指标分别为(12.6±3.5)μmol/L、(49.1±50.4)U/L和(1477.0±810.4)U/L，均较O组显著降低，且差异均有统计学意义(n P均<0.05)。O组灌注后肾组织中MDA含量和SOD活力分别为(0.192±0.018)mmol/g和(0.6±0.3)×10n 3 U/g，A组为(0.162±0.023)mmol/g和(1.7±0.4)×10n 3 U/g；O组TNF-α和IL-6水平分别为(124.376±19.635)ng/g和(4.038±1.026)×10n 3 ng/g，A组为(89.331±13.123)ng/g和(1.774±0.518)×10n 3 ng/g。与O组相比，A组肾组织中MDA含量及TNF-α和IL-6水平降低、SOD活力升高，组间差异均有统计学意义(n P<0.05)。半定量分析结果显示，A组MPO和ICAM-1组织表达均较O组显著降低，差异有统计学意义(n P<0.05)。n 结论:大鼠空气氧合NMP，可有效模拟肾灌注氧气压力的生理状态，降低氧化应激和炎症损伤，更有利于DCD供肾缺血损伤的修复。“,”Objective:To develop an ex vivo normothermic mechanical perfusion(NMP)and compare the effect of air-oxygenated NMP versus oxygen-oxygenated NMP on reducing renal injury from donor after cardiac death(DCD).Methods:All kidneys from DCD rats were subjected to 30 min in situ warm ischemia after cardiac attest.And harvested kidneys were stored for 8h under static cold preservation after NMP for 2h.In experimental groups, kidneys were subjected to either air-oxygenated NMP(group A, n=6)or oxygen-oxygenated NMP(group O, n=6). Sham operation(group C, n=6)and DCD kidneys under static cold preservation without NMP(group SCS, n=6)were employed as controls.The evaluation parameters included creatinine(Cr), aspartate amino transferase(AST)and lactate dehydrogenase(LDH)in perfusate, pathological changes by hematoxylin-eosin(HE)staining, histological criteria, expressions of myeloperoxidase and intercellular adhesion molecular-1(ICAM-1)by immunohistochemistry and Western blot, tumor necrosis factor-alpha(TNF-α)and interleukin-6(IL-6)by enzyme-linked immunoadsorbent assay and level of malondialdehyde(MDA)by thiobarbital method and activity of superoxide dismutase(SOD)by WST-8 in renal tissues.Differences between two groups were analyzed by two-tailed unpaired Student\'s test and differences among more than two groups by one-way ANOVA.Results:Renal arterial oxygen tensions in NMP perfusate were(576.3±68.2)mmHg with oxygen-oxygenation and(137.0±39.1)mmHg with air-oxygenation.There was significant difference(n P<0.05). The pathological injury scores in groups SCS, O and A by HE staining were(7.0±0.1), (5.0±0.9)and(2.5±0.5); injury scores and the expressions of renal proximal tubular epithelial cell vacuolar degeneration in groups O and A were lower than those in group SCS(n P<0.05)and injury score in group A was lower than group O(n P<0.05). In perfusate, the levels of △Cr, △AST and △LDH in groups O and A were(43.9±52.8)μmol/L and(12.6±3.5)μmol/L, (532.3±52.8)U/L and(49.1±50.4)U/L and(9998.0±2014.4)U/L and(1477.0±810.4)U/L.There were significant differences(n P<0.05). In perfused kidneys, the MDA level and SOD activity in groups O and A were(0.192±0.018)mmol/g, (0.162±0.023)mmol/g, (0.6±0.3)×10n 3 U/g, (1.7±0.4)×10n 3 U/g; TNF-α and IL-6 levels in groups O and A were(124.376±19.635)and(89.331±13.123)ng/g, and(4.038±1.026)×10n 3 and(1.774±0.518)×10n 3 ng/g.After air-oxygenated NMP, lower renal damage indices were characterized by a lower MDA level and a higher SOD activity, the lower levels of TNF-α and IL-6 and the lower expressions of MPO and ICAM-1 than those in oxygen-oxygenated NMP(n P<0.05).n Conclusions:NMP with air-oxygenation mimics renal perfusion under physiological conditions and decreases oxidative stress and inflammation injury.It may confer a better retrieval in DCD kidney against warm ischemia injury.