Fas与FasL在兔视网膜缺血再灌注损伤中的表达及rh-bFGF对其表达的影响

目的:探讨重组人碱性成纤维细胞生长因子(rh-bFGF)对兔视网膜缺血再灌注损伤(RIRI)的保护作用。方法:应用前房加压灌注法,升高眼内压,造兔视网膜RIRI模型。外眼及眼底正常纯种大耳白兔66只,随机分为正常假手术组(6只)、RIRI组(30只)和RIRI+rh-bFGF组(30只),均选取右眼为实验眼。RIRI组和RIRI+rh-bFGF组在建立RIRI模型后,前者给予0.9%氯化钠注射液,后者给予rh-bFGF药物治疗。常规HE染色观察视网膜组织细胞形态学的变化,免疫组织化学法检测RIRI组和RIRI+rh-bFGF组6、12、24、48、72 h 5个时间点视网膜组织中Fas、FasL蛋白的表达变化。结果:正常假手术组兔视网膜未见凋亡细胞;RIRI组视网膜的内核层和神经节细胞层可见凋亡细胞,且细胞凋亡在24 h达到高峰。Fas在正常假手术组视网膜组织中未见明显表达;其他2组RIRI后6 h开始有少量表达,至24 h时达到高峰,随后48 h开始下降,到72 h后明显减弱。FasL在正常假手术组视网膜组织中未见明显表达;其他2组RIRI后12 h表达开始升高,至24 h达到高峰,之后略有下降,至72 h依旧可见较高水平表达。RIRI+rh-bFGF组与RIRI组相比较,各时间点凋亡因子阳性表达趋势大致相同,且Fas、FasL表达均明显减弱(P<0.01),2组在6、12、24、48 h各时间点表达差异均有统计学意义(P<0.01)。结论:rh-bFGF对兔RIRI保护作用机制可能与抑制视网膜内Fas、FasL表达有关。

The expressions of Fas and FasL in rabbit retina with ischemia-reperfusion injury,and the effect of recombinant human basic fibroblast growth factor on its expression

Objective:To investigate the protective effects of recombinant human basic fibroblast growth factor(rh-bFGF) on retinal ischemia-reperfusion injury( RIRI) in rabbit. Methods:The models of RIRI in rabbit were established by elevating intraocular pressure. Sixty-six healthy rabbits with normal external ocular and fundus were randomly divided into the sham-operation group(6 rabbits),retinal ischemia-reperfusion injury group( RIRI group,30 rabbits) and rh-bFGF treatment group( RIRI+rh-bFGF group,30 rabbits) . The right eye was selected as the experimental eye. RIRI group and RIRI+rh-bFGF group were treated with 0. 9% sodium chloride injection and rh-bFGF,respectively. Morphological changes of retinal cells and the expressions of Fas and FasL of retinal tissue in sham-operation group,and at 6 h,12 h,24 h,48 h and 72 h time-points of RIRI and RIRI +rh-bFGF groups were detected by HE staining and immunohistochemical method,respectively. Results:No apoptotic cells was found in sham-operation group. Apoptotic cells in RIRI group located mainly in the inner nuclear layer and the ganglion cell layer,and which arrived at peak at 24 h after reperfusion. No obvious expression of Fas in retinal tissue of the sham-operation group was found. After RIRI,little Fas expressing at 6 h,arriving at peak at 24 h,then begaining to decrease at 48 h and significant weakening at 72 h were found. No obvious expression of FasL in retinal tissue of the sham-operation group was found. After RIRI,FasL expression beginning to increase at 12 h,arriving at peak at 24 h,then beginning to decrease and still maintaining a high level at 72 h were found. Compared with the RIRI group,the positive expression trend of apoptotic factors at each time-point in RIRI+rh-bFGF group was similar,the expressions of Fas and FasL in RIRI group and RIRI+rh-bFGF group obviously decreased(P<0. 05). The differences of the expression of Fas and FasL at 6 h,12 h,24 h,48 h and 72 h between RIRI and RIRI+rh-bFGF group were statistical significance(P<0. 01). Conclusions:The protective mechanism of rh-bFGF on RIRI in rabbit may be related to inhibit the expressions of Fas and FasL in retina.