Objective To investigate intermedin (IMD) on hypoxic injury of glomerular endothelial cells in rats. Methods The glomerular endothelial cells in rats were subcultured and randomly divided into the normal group (N group), hypoxia group (H group) and IMD group. The IMD group was divided into 10-8 mol/L (IMD1), 10-7 mol/L (IMD2), and 10-6 mol/L (IMD3) groups according to the final concentration of IMD in the culture medium of the H group. The cell apoptosis was analyzed by flow cytometry. The FITC-BSA fluorescence intensity of the endothelial monolayer was determined. The change of the cell permeability was measured by the ratio of fluorescence intensity of endothelial monolayer. The changes of 4-HNE, ROS and SOD levels in the culture supernatant were determined by ELISA method. The mRNA expression of the hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) was determined by real-time polymerase chain reaction (RT-PCR). The protein expression of HIF-1αand VEGF was determined by immunocytochemistry for semi-quantitative analysis. Results Compared with N group, the cell apoptosis rate reduced in IMD1, IMD2, and IMD3 groups (P<0.05); the cell permeability was increased (P<0.05), the 4-HNE and ROS levels were increased, and the SOD level was decreased in the culture supernatant of the H groups (P<0.05); the mRNA relative expression and protein content of HIF-1α and VEGF in the IMD2 group were increased (P<0.05). Compared with the H group, the cell apoptosis rate was reduced (P<0.05), the cell permeability was decreased (P<0.05), the 4-HNE and ROS levels were decreased, and the SOD level was increased in the IMD1, IMD2 and IMD3 groups (P<0.05); the mRNA relative expression and protein content of HIF-1α and VEGF in the IMD2 group were increased (P<0.05). According to correlation analysis, the mRNA relative expression of HIF-1α and VEGF and the cell apoptosis rate showed a strong negative correlation ( r=-0.919 and-0.911, respectively, P<0.05). Conclusion IMD may reduce hypoxic injury of glomerular endothelial cells, and protect glomerular endothelial cells, which is correlated with its up-regulation of VEGF and HIF-1α.%目的：研究中介素（IMD）对大鼠肾小球内皮细胞（rRGEC）缺氧损伤的作用。方法 rRGEC传代培养后，随机分为正常组（N组），缺氧组（H组）及IMD组，根据培养液中IMD的终浓度将缺氧处理组分为10-8 mol/L（IMD1）、10-7 mol/L（IMD2）、10-6 mol/L（IMD3）组。流式细胞仪分析细胞凋亡；检测内皮单层底顶室异硫氰酸荧光素（FITC）-BSA荧光强度，以底顶室荧光强度比值的变化来表示细胞通透性的变化；酶联免疫吸附（ELISA）法检测细胞上清液中4-羟壬烯醛（4-HNE）、活性氧（ROS）、超氧化物歧化酶（SOD）变化；实时荧光定量PCR（RT-PCR）检测细胞细胞缺氧诱导因子-1α（HIF-1α）及血管内皮生长因子（VEGF）mRNA的表达；免疫细胞化学法检测HIF-1α及VEGF蛋白表达并进行半定量分析。结果与N组相比，IMD1、IMD2、IMD3组细胞凋亡率均降低（P＜0．05）；H、IMD1、IMD2、IMD3组细胞通透性均增加（P＜0．05），H组上清中4-HNE、ROS升高，SOD降低（P＜0．05）；IMD2组HIF-1αmRNA相对表达量及蛋白含量增高（P＜0．05），VEGFmRNA相对表达量及蛋白含量增高（P＜0．05）；与H组相比，IMD1、IMD2、IMD3组细胞凋亡率均降低（P＜0．05），细胞通透性降低（P＜0．05），4-HNE、ROS降低，SOD升高（P＜0．05），IMD2组HIF-1αmRNA相对表达量及蛋白含量增高（P＜0．05），VEGF mRNA相对表达量及蛋白含量增高（P＜0．05）。相关分析发现HIF-1αmRNA、VEGF mRNA相对表达量与细胞凋亡率呈较强负相关（r=-0．919、-0．911，P＜0．05）。结论 IMD可减轻肾小球内皮细胞缺氧损伤，保护肾小球内皮细胞，与其上调VEGF与HIF-1α生成有关。
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