重组人碱性成纤维细胞生长因子对兔视网膜缺血再灌注损伤的保护作用

Protective Effect of Recombinant Human Basic Fibroblast Growth Factor on Retinal Ischemia-reperfusion Injury in Rabbits

目的探讨重组人碱性成纤维细胞生长因子(recombinant human basic fibroblast growth factor,rh-bFGF)对兔视网膜缺血再灌注损伤(retinal ischemia reperfusion injury,RIRI)的保护作用。方法选取健康纯种大耳白兔66只,随机分为假手术组6只,RIRI组30只,rh-bFGF组30只。通过升高眼压的方法制作兔RIRI模型,RIRI组予0.9%氯化钠注射液,rh-bFGF组予rh-bFGF治疗,假手术组仅用5号头皮针从耳前方角巩膜缘内刺入前房,之后缓慢拔除针头。RIRI组和rh-bFGF组在RIRI后6 h、12 h、24 h、48 h、72 h常规HE染色观察视网膜组织形态变化,SABC免疫组织化学法检测视网膜组织中凋亡抑制基因Bcl-2和促凋亡基因Bax蛋白表达及Bcl-2/Bax的变化。结果假手术组视网膜未见凋亡细胞;RIRI组视网膜凋亡细胞主要出现在内核层和神经节细胞层,且在24 h达到高峰;rh-bFGF组与RIRI组比较,观察各时间点细胞损伤情况基本相似。Bcl-2和Bax在正常视网膜组织中几乎不表达,在RIRI后6 h开始表达,24 h达到高峰,48 h开始下降,72 h后表达明显减弱。rh-bFGF组与RIRI组比较,Bcl-2表达明显增强,而Bax表达减弱(P均<0.05)。结论 Bcl-2和Bax参与了RIRI的调控,rh-bFGF可通过上调Bcl-2表达及下调Bax表达,使Bcl-2/Bax比值升高,起到保护视网膜组织的作用。

Objective To explore the protective effect of recombinant human basic fibroblast growth factor（ rh-bFGF） on retinal ischemia-reperfusion injury（ RIRI） in rabbits. Methods The 66 healthy purebred rabbits were randomly divided into shamoperation group（ n =6）,ischemia-reperfusion model group（ n =30） and rh-bFGF treatment group（ n =30）. The RIRI models were established by elevating intraocular pressure,the ischemia-reperfusion model group was injected with 0. 9% sodium chloride injection; rh-bFGF drug therapy was performed in rh-bFGF treatment group; the sham-operation group only received the 5thscalp heedle from ear piercing the anterior chamber angle in front of the sclera edge,and then the needle was slowly removed. Retina histopathological changes were observed by routine hematoxylin and eosin stain 6 h,12 h,24 h,48 h and 72 h after RIRI in ischemia-reperfusion model and rh-bFGF treatment groups. Expressions of inhibiting gene Bcl-2 and stimulative gene Bax and changes of Bax/Bcl-2in retinal tissues were detected with SABC immunohistochemical method. Results No apoptotic cell was found in sham-operation group; apoptotic cells mainly existed in the inner nuclear layer and the ganglion cell layer,and apoptotic cells reached the peak24 h after reperfusion; the rh-bFGF treatment groups had the similar condition with the ischemia-reperfusion model group in cell injury at each observational time. No expressions of Bcl-2 and Bax positive cells were found in normal retina tissues; the expressions were found 6 h after reperfusion,and the expressions reached the peak 24 h after reperfusion,and began to descented 48 h after reperfusion,and the decrease was obvious 72 h after reperfusion. Bcl-2 expression was significantly stronger,while Bax expression was significantly reduced in rh-bFGF treatment group,compared with those in ischemia-reperfusion model group（ P 0. 05）. Conclusion Bcl-2 and Bax protein are involved in the RIRI regulation. The retina tissue can be protected with Bcl-2 expression of upregulation and the Bax expression of down-regulation by rh-bFGF,which can increase the Bcl-2 /Bax ratio.