色素上皮源性生长因子在低压性缺氧成年大鼠视网膜的表达

Pigment epithelium-drived factor expression in the retina in response to hypobaric hypoxia

目的探讨成年大鼠在低压性缺氧后，色素上皮源性生长因子在其视网膜的表达情况。方法成年Wistar大鼠48只随机分成6组，每组8只，其中正常对照组8只，其余5组在暴露于低氧环境（氧气体积分数为7％～9％）2h后，分别于3h、24h、3d、7d和14d，通过实时荧光定量逆转录聚合酶链反应，蛋白免疫印迹法和免疫组化的方法检测色素上皮源性生长因子（PEDF）在视网膜的表达情况。结果免疫组化显示PEDF在正常及缺氧组大鼠视网膜神经节细胞层、内网层、外网层、内核层和光感受器层有表达；在暴露于低氧性环境后的3h、24h、3d、7d和14d，成年大鼠视网膜PEDF mRNA水平与正常对照组相比，分别减少17．3％、28％、44％、46％和51％（P值均〈0．05）；PEDF蛋白质水平较正常对照组分别减少了21．6％、37．3％、39．8％、42．6％、43．9％（P值均〈0．05）。结论：这次实验结果表明缺氧可以使成年大鼠视网膜PEDF的表达下调。

Objective The present study was undertaken to examine the expression of pigment epithelium-derived factor（PEDF） in the retina of adult rat following hypobaric hypoxic exposures. Methods Forty-eight adult Wistar rats were divided into 6 groups randomly （8 rats in each group）, of which 5 groups （40 rats） were subjected to hypobaric hypoxia for 2 hours following which expression of PEDF in the retina was investigated from 3 hours to 14 days by real time RT-PCR, western blotting and immunohistochemistry. Results PEDF mRNA and protein expression in the retina was decreased at 3 hours to 14 days following exposure to hypoxia. Compared with normal control group （1. 130 ± 0.130 ）, PEDF mRNA expression decreased to 0. 83 ±0. 05 at 3 hours,0. 72 ±0. 04 at 24 hours,0. 56 ±0. 04 at 3 days,0. 54 s0. 05 at 7 days and 0. 49 s0. 05 at 14 days respectively; Compared with normal control group（ 1.90±0. 02）, PEDF protein expression decreased to 1.49 ±0.02 at 3 hours,1.19 ±0.05 at 24 hours,1.15 ±0.05 at 3 days,1.09± 0. 06 at 7 days and 1.07 ± 0. 03 at 14 days respectively. Conclusions The findings of this study indicate hypoxia can downregulate PEDF in adult retina.