bFGF在持续高眼压下对兔视网膜神经节细胞的保护作用

Protective effect of bFGF on retinal ganglion cells under high intraocular pressure in rabbits

目的研究碱性成纤维细胞生长因子(bFGF)在持续高眼压下对兔视网膜神经节细胞的保护作用。方法健康新西兰大白兔27只,其中24只(48眼)卡波姆注入前房法制成持续高眼压动物模型,随机分为2组,每只兔一眼为高眼压组(各24眼),另一眼为bFGF实验组(各24眼);另3只(6眼)为正常组。bFGF实验组在建模过程中及成功后1、2、3周玻璃体腔内注射bFGF各1次,正常组在相应的时间仅玻璃体腔内注入与bFGF实验组等体积的磷酸缓冲生理盐水(PBS)。术后每日固定时间测量眼压,将眼压维持在30mmHg以上。分别于建模后1、2、3、4周随机处死6只兔子。完整摘除眼球行常规HE染色观察视网膜神经节细胞形态变化并计数存活细胞数目,免疫组织化学染色检测视网膜神经节细胞Bcl-2凋亡基因的表达。建模后4周行电镜观察视网膜神经节细胞超微结构的变化。结果光镜:建模后两组神经节细胞数目均较正常组减少,自2周后高眼压组与bFGF实验组比较差异有统计学意义(P<0.05)。免疫组织化学:比较视网膜神经节细胞抗凋亡蛋白(RGCsBcl-2)基因蛋白表达的阳性目标面积构成比,第3周时bFGF实验组Bcl-2基因蛋白仍保持较高水平的表达,两组比较差异有统计学意义(P<0.01)。电镜:术后4周bFGF实验组改变明显轻于高眼压组,细胞器较对照组丰富,部分线粒体仍可见完整嵴。结论bFGF作为一种神经营养因子,对高眼压下兔视网膜神经节细胞具有保护作用。

Objective To observe the protective function of basic fibroblast growth factor （bFGF） on retinal ganglion cells under high intraocular pressure （HIP） in rabbits. Methods 27 healthy New Zealand rabbits were used in this study. Among them,3 rabbits were selected as the （normal） control group. In the other 24 rabbits,carbomer was in-jected into the anterior chamber to make HIP models. The two eyes of each HIP model were randomly selected as the HIP eye and the bFGF treatment eye,and 0. 1 mL PBS and 0. 1 mL bFGF were injected into the two anterior chambers respectively 1,2 and 3 weeks after operation. The intraocular pressure was observed everyday and kept at more than 30 mmHg. Then 6 rabbits were sacrificed each week to count the number and observe the morphologic change of retinal ganglion cells. Results The number of retinal ganglion cells was decreased in both bFGF treatment eyes and HIP eyes especially in the HIP eyes from the 2nd （2ed） week（P〈0. 05）. Bcl-2 expression was higher in bFGF treatment eyes than in HIP eyes from the 3rd week（P〈0. 01）. Under an electron microscope,the morphology of retinal ganglion cells was less changed in （the） bFGF treatment eyes and complete crista was seen in part of the mitochondria. Conclusion bFGF can protect retinal ganglion cells against HIP as a kind of neurotrophic factor.