兔视网膜光凝术后GFAP和CTGF蛋白的表达

目的：探讨色素家兔视网膜光凝术后Müller细胞胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)和结缔组织生长因子（connective tissue growth factor，CTGF）)在激光斑的表达。方法:采用倍频532nm绿激光光凝色素家兔视网膜后极部30点（光斑效应为Tso分级Ⅲ级），建立色素兔视网膜光凝Ⅲ级光斑效应动物模型。24只有色家兔右眼为视网膜光凝眼、左眼为正常对照眼。按术后观察时间1,3,7,14,21,28d分为6个亚组，各组动物于光凝术后相应的时间点处死，取出眼球进行免疫组织化学方法测定GFAP和CTGF的表达，Pearson直线相关分析两者之间有无相关性。结果:GFAP蛋白在色素家兔正常对照眼神经节细胞层弱表达，光凝后3d，激光斑Müller细胞表达GFAP，表达持续增强到光凝术后28d。光凝后3d，CTGF在光斑处弱表达，持续增强至术后28d，CTGF阳性表达在视网膜光凝斑的视网膜神经节细胞层（GCL）、成纤维细胞、视网膜色素上皮层（RPE）细胞和无定形的胶原基质。CTGF蛋白在正常对照眼无表达。 Pearson直线相关分析：视网膜光凝斑GFAP与CTGF表达强度在时序上呈密切正相关（r=0.786，P<0.01）。结论: CTGF与GFAP参与了视网膜光凝术后激光斑损伤修复的调控过程。可能是视网膜神经胶质瘢痕形成的一个重要的病理学基础。

Expression of glial fibrillary acidic protein and connective tissue growth factor in pigmented rabbitsretina after photocoagulation

AIM: To investigate the expression of glial fibrillary acidic protein(GFAP) and connective tissue growth factor (CTGF) in pigmented rabbitsretinal laser scar after photocoagulation. METHODS: The model of retinal photocoagulation in pigmented rabbit was established in right eyes by frequency doubled 532nm laser with laser lesion effect of Tso grade Ⅲ photocoagulated spots at a wavelength of 532nm,for a duration of 0.05 seconds, at a power of 450mw,making a 75μm diameter spot. The left eyes were control group eyes. Twenty-four pigmented rabbits were randomly divided into six groups at the postoperative days 1,3,7,14,21,28 after photocoagulation. The eyes were enucleated at the schedule time,fixed and cut into sections.Immunohistochemical examination was used to detect the expression of CTGF and GFAP. Pearson linear regression analysis was performed to determine possible relationship between GFAP and CTGF. RESULTS:The Müller cells expressed GFAP at 3 days after photocoagulation and lasted for at least 28 days. There was weak expression in end feet of Müller cells in retina of normal control group. The expression of CTGF was detected in retinal lesion at 3 days after photocoagulation and increased with time. But the expression of CTGF in normal control group was not detected. The expression of GFAP protein had markedly positive relationship with CTGF (r=0.786,P<0.01). CONCLUSION:GFAP and CTGF may take part in regulating recovery of retinal laser scar after photocoagulation in pigmented rabbits.