雌激素相关受体γ和ATP依赖性K＋通道Kcnj1在肾脏缺血及再灌注损伤中的作用

The role of estrogen related-receptor γ and ATP-dependent K ＋ channel Kcnjl in renal ischemia. reperfusion injury

目的探讨雌激素相关受体和ATP依赖性K＋通道Kcnj1在肾脏缺血再灌注过程中的相关性表达以及其在参与缺血预处理保护中可能发挥调节的作用。方法使用免疫组化方法检测ERR5,在小鼠肾脏组织中的表达；使用逆转录聚合酶链反应（RT—PCR）方法检测人肾小管上皮细胞（HK-2）在缺氧环境下（1％O2）ERRγ和Kcnj1的表达；建立ERRs／缺陷杂合子小鼠模型、ER脚完全敲除小鼠模型，将野生型小鼠、ERRs／缺陷杂合子小鼠、ERR叮完全敲除小鼠分别做预处理一缺血再灌注模型，通过观察雌激素相关受体1（ERRγ）和ATP依赖性K＋通道Kcnj1在肾脏缺血再灌注损伤中表达变化的关系，采用肾组织标本HE染色观察肾组织病理损伤、免疫组化以及RT-PCR检测肾组织ERRγ／和Kcnjl表达水平的变化。结果ERRγ在小鼠肾脏组织中主要表达于。肾小管，肾小管细胞（HK-2）缺氧后ERRγ和KATP分子Kcnj1表达分别降低59％和29．5％；动物模型实验中，野生型小鼠肾脏早期缺血，肾小管细胞ERRs／和Kcnj1的表达分别下调31．9％和11．0％；缺血再灌注后肾小管细胞ERR7和Kcnj1的表达分别下调33．2％和19．1％；在肾小管细胞中过表达ERRγ，ERR1表达升高89％后，Kcnj1的表达升高72．5％。ERRγ完全敲除小鼠的肾脏Kcnj1表达下降75．7％；ERRγ基因缺陷小鼠中肾脏Kcnj1的表达虽然稳定，但缺血预处理不能干预肾脏缺血再灌注损伤。结论ERRγ与缺血预处理保护肾脏缺血再灌注损伤存在密切关系，并且可能是其中的调节因素，探索调节该通路对缺血再灌注损伤的保护作用；以期为开发预处理药物提供理论依据。

Objective To investigate the correlation between estrogen related-receptor γ （ERR γ） and ATP-dependent K＋ channel Kcnj1 in renal ischemia-reperfusion injury and its possible role in regulating ischemic preconditioning. Methods The expression of ERRγ in kidney tissues was detected by immunohistochemistry. The expressions of ERRγ and Kcnj1 in human renal tubular epithelial cells （HK-2） under hypoxia （ 1% O2） were detected by RT-PCR. The ERRγ-deficient heterozygous mice model and the ERRγ-deficient completely mice model were established. The pretreatedischemia-reperfusion model were constructed in wild-type mice, ERRγ-deficient heterozygous mice and ERRγ-deficient completely mice, respectively. Renal injury was observed under a light microscope with PAS staining. ERRγ/and Kcnjl were tested by immunohistochemistry and RT-PCR. Results ERRγ in mice kidney tissue was mainly expressed in renal tubules, and the expressions of ERRγ and Kcnjl were decreased 59% and 29. 5% respectively after hypoxia in the renal tubular cells （HK-2）. In the animal model, the expressions of ERRγ and Kcnjl were decreased 31.9% and 11% in early ischemic mice kidney tubular cells of wild type. The expressions of ERRs, and Kcnj1 in renal tubular ceils were decreased 33.2% and 19. 1% after ischemia and reperfusion. When ERRγ were overexpressed in renal tubular cells, ERRγ was increased by 89%, and the expression of Kcnjl was increased by 72. 5%. The expression of Kcnjl was decreased by 75.7% in ERRγ-deficient completely mice. However, Kcnjl expression in renal tissue of ERR-γ-deficient mice was stable, but ischemic preconditioning failed to interfere with renal ischemia-reperfusion injury. Conclusion ERRγ-Kcnj1 is closely related to ischemic preconditioning and protects renal ischemia-reperfusion injury, and may be one of the regulatory factors. To explore the protective effect of the regulating pathway on ischemia reperfusion injury couldprovide a theoretical basis for the development of drug pretreatment.