缺氧对视网膜Müller细胞VEGF和PEDF表达的影响

Effect of hypoxia on the expressions of VEGF and PEDF in cultured retinal Müller cells

目的探讨缺氧对体外培养的大鼠视网膜M櫣ller细胞血管内皮生长因子(vas-cular endothelial growthfactor,VEGF)和色素上皮衍生因子(pigment epitheliumderived fac-tor,PEDF)表达的影响。方法采用RT-PCR和Western印迹分析方法分别对不同缺氧时间视网膜M櫣ller细胞VEGF和PEDF的mRNA及蛋白水平进行测定。结果M櫣ller细胞VEGF mRNA及蛋白表达在缺氧12h后明显升高,缺氧24h更为显著,24h时2者分别为对照组的2.12倍(P<0.05)和1.70倍(P<0.05)。PEDF mRNA及蛋白表达在缺氧6h后明显下降(P<0.05),缺氧24h下降更为显著,24h时2者分别为对照组的0·11倍(P<0.01)和0.54倍(P<0.05)。结论缺氧条件下,体外培养的大鼠M櫣ller细胞VEGF和PEDF表达失衡,PEDF表达下降,同时VEGF表达增加,2者的表达失衡可能在视网膜病理性新生血管形成过程中起一定作用。

Objective To explore the effect of hypoxia on the expressions of pigment epithelium derived factor （PEDF） and vascular endothelial growth factor （VEGF） in the cultured rat retinal Mueller cells. Methods Rat Mueller cells were cultured under hypoxia. RToPCR and Western-blot analysis were used to measure the PEDF and VEGF levels at different times in cultured Mueller cells under hypoxic condition. Results The levels of VEGF mRNA and protein were remarkably increased when the Miiller cells were exposed under hypoxic condition for 12 hours,and after 24 hours, the increase was much more significant that the level of VEGF mRNA was 2.12 times compared with the control（P〈0.05）and the level of VEGF protein was 1.70 times of that in the control（P〈0.05）. The levels of PEDF mRNA and protein were remarkably decreased 6 hours after the hypoxia,and after 24 hours, the decrease was much more significant that the level of PEDF mRNA was 0.11 times compared with the control（P〈0.01）and the level of VEGF protein was 0.54 times of that in the control （P〈0.05 ）. Conclusion The imbalance of expression between VEGF and PEDF in Mueller cells under hypoxic condition may play a potential role in neovascularization of diabetic retinopathy.