目的：探讨生长激素释放多肽(Ghrelin)对高糖环境下人视网膜色素上皮(retinal pigment epithelium，RPE)细胞氧化应激的影响。

方法：将体外培养的RPE细胞分为阴性对照组、高糖组、Ghrelin低浓度组、Ghrelin高浓度组。通过CCK-8法检测细胞存活率，氧敏感荧光探针H₂DCFDA染色法观察细胞氧化损伤程度，流式细胞技术检测细胞内活性氧(reactive oxygen species，ROS)的变化，分光光度计比色法检测细胞内超氧化物歧化酶(superoxide dismutase，SOD)活力和丙二醛(malondialdehyde，MDA)含量。

结果：CCK-8结果显示，分别用10^-9mol/L、10^-6mol/L Ghrelin预处理后，RPE细胞存活率分别为54.79%±3.43%和79.16%±3.29%，与高糖组(41.65%±3.42%)比较，差异均有统计学意义(P<0.05)。H₂DCFDA荧光探针染色结果显示，Ghrelin预处理后RPE细胞内ROS生成量下降，氧化损伤细胞减少。分光光度计比色法结果显示，与高糖组相比，Ghrelin组细胞SOD活力增加，MDA含量下降。

结论：Ghrelin可以抑制高糖诱导的人RPE细胞氧化损伤，其在糖尿病视网膜病变的发生发展过程中可能具有一定的细胞保护作用。

METHODS: RPE cells were cultured and divided into the negative control group, high sugar group, Ghrelin low dose group(10^-9 mol/L)and high dose group(10^-6 mol/L). Cells survival rate were detected by CCK-8 colorimetry, cells oxidative damage were observed by oxygen sensitive fluorescence probe H₂DCFDA staning, changes of intracellular reactive oxygen species(ROS)were detected by H₂DCFDA staining, super oxide dismutase(SOD)activity and malondialdehyde(MDA)content were detected by spectrophotometer colorimetry.

RESULTS: CCK-8 results showed that RPE cells survival rate increased to 54.79%±3.43% and 79.16%±3.29% after treated with 10^-9 mol/L, 10^-6 mol/L Ghrelin, the difference was statistically significant compared with high glucose group(41.65%±3.42%)(P<0.05). H₂DCFDA fluorescent probe dying showed that Ghrelin reduced ROS generation in RPE cells and decreased oxidative damage cells. Spectrophotometer colorimetric method showed that according to the high sugar group, SOD activity increased and MDA content decreased in Ghrelin group.

CONCLUSION: Ghrelin could inhibit high glucose-induced oxidative damage in human RPE cells, which has protective effect on the process of the occurrence and development of diabetic retinopathy.