中文摘要：

目的 观察转化生长因子β1（TGF-β1）诱导视网膜色素上皮（RPE）细胞间质样转分化（EMT）过程中Rac1在其细胞学行为改变中的作用.方法 人RPE-19细胞分为空白组、TGF-β1组、TGF-β1＋NSC23766组、NSC23766组.所有实验于加入TGF-β1前2h给予NSC23766以封闭Rac1受体.免疫荧光、蛋白免疫印迹法检测细胞中α-平滑肌肌动蛋白（α-SMA）表达;细胞划痕、侵袭及凝胶收缩实验,观察NSC23766对细胞迁徙、侵袭、凝胶收缩作用.结果 TGF-β1组细胞中α-SMA荧光表达较空白组、TGF-β1＋ NSC23766增强,差异有统计学意义（F=825.314,P=0.003）;细胞划痕实验结果显示,TGF-β1组细胞间距小于TGF-β1＋ NSC23766组,差异有统计学意义（P24h=0.04,P48h =0.001）;与空白组细胞间距比较,差异无统计学差异（P=0.278）.细胞侵袭实验结果显示,TGF-β1组穿过纤维膜的细胞数与空白组、TGF-β1＋ NSC23766组、NSC23766组穿过纤维膜的细胞数比较,差异无统计学意义（F=0.371,P=0.055）.凝胶收缩实验结果显示,TGF-β1组能明显增加细胞的促凝胶收缩能力,组间差异有统计学意义（F=40.473,P=0.014）,TGF-β1组相对TGF-β1＋ NSC23766组,差异有统计学意义（P=0.022）.结论 Rac1在TGF-β1诱导RPE细胞凝胶收缩改变中发挥作用;NSC23766可通过调控Rac1活化抑制RPE细胞学行为的改变.

英文摘要：

Objective To study the role of Racl in the epithelial-mesenchymal transition （EMT） process of retinal pigment epithelial cells （RPE） induced by transforming growth factor β （TGF-β）.Methods Human ARPE-19 cells were divided into 4 groups including control group,TGF-β group,TGF-β ＋ NSC23766 group,NSC23766 group.NSC23766 was added to medium 2 hours before TGF-β treatment to block the Rac1 receptors.α-smooth muscle actin （α-SMA） expression was measured by immunofluorescence and Western blot.Cell scratch assay,invasion assay and gel contraction experiments were used to measure cell migration,invasion,cell contraction.Results The expression of α-SMA was higher in TGF-β group,compared with the control group,TGF-β ＋ NSC23766 group （F=825.314,P＜0.05）.Cell scratch assay showed that the cellular gap was less in GF-β group,compared with the control group,TGF-β ＋ NSC23766 group,NSC23766 group （F=177.351,P＜0.05）.Cell invasion assay showed that,the number of cells pass through the fiber membrane was the same in TGF-β group and other 3 groups （F=0.371,P=0.055）.Gel contraction assay showed that TGF-β can promote the cellular contraction,compare to the control group,TGF-β ＋ NSC23766 group,NSC23766 group,the difference was statistically significant （F=40.473,P＜0.05）.Conclusion Rac1 play a role in TGF-β-induced behavioral changes of RPE cells; NSC23766 inhibit RPE cellular behavior change by regulating Rac1 activation.