中文摘要：

目的观察磷酸化信号转导与转录激活因子3（STAT3）在激光诱导的大鼠脉络膜新生血管（CNV）中的表达，探讨STAT3在CNV中可能的作用。方法建立激光诱导的大鼠CNV模型，免疫荧光法观察CNV生成早期磷酸化STAT3的表达。建立细胞缺氧模型，细胞培养液中加入Janus激酶2（JAK2）特异性阻断剂AG490后培养1、3、6、12、24h。流式细胞仪检测视网膜色素上皮（RPE）细胞的增生指数，反转录聚合酶链反应（RT—PCR）检测缺氧诱导因子-1α（HIF-1α）和VEGF的mRNA表达，蛋白质免疫印迹法检测HIF-1α蛋白表达，酶联免疫吸附试验检测细胞培养液上清液中血管内皮生长因子（VEGF）的含量。结果激光光凝后3d，磷酸化STAT3高表达于大鼠CNV区域。阻断JAK2／STAT3信号转导通路后，缺氧条件下人RPE细胞随时间增生指数明显降低（t=1．472，3．566，2．391，6．420；P=0．054，0．038，0．042，0．016）。随缺氧时间增加，HIF-1α和VEGFmRNA表达逐渐增强。采用AG490阻断JAK2／sTAT3信号转导通路后，缺氧条件下人RPE细胞HIF-1α mRNA和VEGFmRNA的表达、HIF-1α蛋白的活化均受明显抑制（t=0．07，0．02，0．01，P〈0．05）；细胞培养上清液中VEGF含量显著降低（t=1．330，1．106，2．828，7．742，5．610，6．894，P=0．082，0．063，0．014，0．002，0．016，0．011）。结论STAT3可能参与了CNV的发生，这一过程部分是通过JAK2／STAT3信号转导通路调控RPE细胞HIF-1α和VEGF表达而实现的。

英文摘要：

Objective To investigate the possible effects of phosphorylated signal transduction and activator of transcription3 （STAT3） in the formation of choroidal neovascuarization （CNV） induced by photocoagulation in rats. Methods The CNV model in rats induced by photocoagulation was established, and the expression of phosphorylated STAT3 at the early stage in CNV were observed by immunofluorescence. To set up the hypoxia model, the specific inhibitor of Janus kinase 2 （JAK2）, AG490 was mixed into cell culture fluid and then cultured for 0, 1 hour, 3, 6, 12, and 24 hours. Retinal pigment epithelial （RPE） cells proliferation activity were detected by flow eytometry （FCM）; the expression of hypoxia-inducible factor （HIF）-1α and vascular endothelial grow factor （VEGF） mRNA were detected by reverse transeriptase polymerase chain reaction （RT-PCR） ; the expression of HIF-1α protein was detected by Western blot; the content of VEGF in the supernatant of cell culture fluid was measured by enzyme linked immunosorbent assay （ELISA）. Results Phosphorylated STAT3 highly expressed in CNV areas in rats 3 days after the photocoagulation. The proliferation activity of human RPE cells under hypoxia condition significantly decreased after inhibition of JAK2/STAT3 signal transduction pathway （t = 1. 472, 3. 566, 2. 391, 6. 420; P=0.054, 0.038, 0.042, 0.016）. The expression of HIF-1α and VEGF mRNA increased gradually with increasing time of hypoxia; while the expression of HIF-1α and VEGF mRNA and the activation of HIF-1α protein in cultured human RPE cells with the JAK/STAT3 signal transduction pathway blocked by AG490 were suppressed obviously under hypoxia condition （t=0.07, 0.02, 0.01, P〈 0.05） ; the content of VEGF in RPE cells supernatant decreased significantly （t=1. 330, 1. 106, 2. 828,7.742, 5.610, 6.894; P=0.082, 0.063, 0.014, 0.002, 0.016, 0.011）. Conclusion STAT3 may be involved in CNV formation, which may partly dependent on JAK2/STAT3 signal transduction pathway regulatin