一氧化碳释放分子2减轻小鼠肾脏缺血再灌注损伤

Carbon monoxide-releasing molecule CORM-2 protects against renal ischemiareperfnsion injury in mice

目的探讨一氧化碳释放分子2（CORM-2）对小鼠肾脏缺血再灌注损伤的作用及其效应。方法制备Balb／c小鼠原位肾脏缺血再灌注模型：在32℃下完全阻断小鼠左肾血流40min，然后恢复血流灌注，同时切除小鼠对侧肾脏。小鼠分别于术前1h经尾静脉注射CORM-2溶液（CoRM-2组）或失活CORM-2溶液（iCORM-2组），另设假手术组作为对照。再灌注24h后，检测各组小鼠肾功能，取肾脏组织行HE和原位末端转移酶标记染色检查，评价其肾脏组织损伤程度。再灌注1、3、7d后，取小鼠肾脏组织进行免疫组织化学和免疫荧光检测，观察小鼠肾缺血再灌注损伤过程中炎症反应的情况。结果IRI组出现明显肾功能损害，其小鼠血肌酐和尿素氮水平与假手术组相比较，差异均有统计学意义（P〈0．05）；CORM-2组肾功能损害程度减轻，其小鼠血肌酐和尿素氮水平低于IRI组和iCORM-2组（P〈0．05）。常规病理学检查发现，IRI小鼠肾脏组织中肾小管上皮细胞发生凋亡坏死；CORM-2组肾小管上皮细胞的凋亡减轻。IRI组小鼠缺血再灌注损伤早期（再灌注1d和3d），肾脏组织中出现大量MPO阳性中心粒细胞和肿瘤坏死因子α，介导急性炎症反应。CORM-2组MPO阳性中性粒细胞浸润和肿瘤坏死因子α产生明显减少。结论CORM-2可以减轻小鼠肾缺血再灌注中的炎症反应，发挥保护作用。

Objective To investigate if the administration of CORM-2 can provide protection against renal ischemia-reperfusion injury （IRI）. Method Murine renal ischemia was induced by clamping left renal pedicles for 40 rain with vascular micro clamps at 32 C, then the contralateral kidney was removed. CORM-2 or vehicle was administered via intravenous infusion 1 h before the onset of ischemia. The blood plasma and renal samples were obtained at 24 h after reperfusion to assess renal function and cellular injury. Plasma Cr and BUN levels, HE and TUNEL were performed to estimate the magnitude of renal damage. Kidneys were retrieved from indicated animals at various time points after renal IRI, and the sections were prepared for histological evaluation. MPO staining procedures were performed to assess the neutrophils infiltration in the renal IRI. Besides, Immunofluorescent stain of TNF-α was performed on the kidneys which were retrieved from indicated animals to determine the production of inflammatory mediators in renal I/R. Results The plasma Cr and BUN were significantly increased at 24 h after reperfusion in IRI control mice, and CORM-2 treatment could markedly diminish the increase of plasma Cr and BUN in mice subjected to I/R. In parallel, histological analysis demonstrated that CORM-2 treatment markedly reduced apoptosis of the renal tubular epithelium cells and hemorrhage. IRI caused marked infiltration and accumulation of the MPO-positive neutrophils in renal interstitiurru Administration of CORM-2 before ischemia dramatically inhibited neutrophils infiltration as compared with IRI or iCORM-2 group. Furthermore, we confirmed that CORM-2 markedly decreased production of TNF-α. Conclusion Carbon monoxidereleasing molecule CORM-2 could ameliorate inflammation to protect against the renal IRI in mice.