碱性成纤维细胞生长因子对鼠视网膜缺血再灌注损伤的治疗作用

目的　探讨碱性成纤维细胞生长因子 (bFGF)在大鼠视网膜缺血再灌注损伤中的治疗作用。方法　 4 0只大鼠采用升高眼内压的方法建立大鼠视网膜缺血再灌注模型作为手术组 ,该组大鼠左眼于玻璃体腔中注入赋形剂 (缺血组 ) ,右眼于玻璃体腔中注入bFGF(治疗组 ) ;另外 4只大鼠为正常组。手术组于再灌注后 1、6、12、2 4及 72h分别应用末端脱氧核酸转移酶介导的脱氧三磷酸尿苷缺口末端标记法检测视网膜组织中凋亡细胞的表达 ,采用过氧化物酶标记的链酶卵白素免疫组化方法检测caspase 3的表达 ,使用原子吸收光度计测定细胞内钙离子的变化。 结果　缺血组再灌注 6h大鼠视网膜出现凋亡细胞 ,并随时间依次增加 ,至 2 4h达高峰 ,72h时几乎未发现凋亡细胞。caspase 3表达改变与凋亡细胞表达相似。细胞内钙离子含量于再灌注后 1h开始升高 ,至 2 4h达到高峰 ,72h出现下降。治疗组各观察指标变化规律基本同上 ,但再灌注 12、2 4h时的凋亡细胞数目明显低于缺血组 (P <0 0 5 ) ;于 6、12及 2 4h ,caspase 3的表达较缺血组明显下降 (P <0 0 5 ) ;于 6、12、2 4及 72h ,细胞内钙离子含量均明显低于缺血组 (P <0 0 5 )。结论　细胞凋亡可能在视网膜缺血再灌注损伤过程中起重要作用 ,bFGF可通过对细胞内钙离子、自由基及凋

An experimental study of the therapeutical effect of bFGF in retinal ischemia/reperfusion injury

Objective To investigate the therapeutical effect of basic fibroblast growth factor (bFGF) on retina ischemia/reperfusion injury. Method Experimental retinal ischemia/ reperfusion injury was induced by increasing intraocular pressure of rats eyes. 48 rats were divided into groups of control, ischemia/ reperfusion and bFGF-treated, randomly. Apoptotic cells were detected using the TdT-dUTP terminal nick-end labeling at 1 hour, 6 hours, 12 hours, 24 hours, and 72 hours after reperfusion. The expression of caspase-3 at specified times was determined by Streptavidin Peroxidase immunohistochemistry. Atomic absorption spectrum method was used to evaluate the intracellular calcium changes of retinal tissues. Results In ischemia group, apoptotic cells began to appear at 6th hour after reperfusion and increased progressively with time. The number of apoptotic cells reached the peak 24 hour after reperfusion, and no apoptotic cells could be found at 72 hours. Changes in caspase-3 expression followed a similar trend. The intracellular calcium level of rat retina began to increase at 1 hour after reperfusion, and continued to increase with the reperfusion time.At 24 hours after reperfusion the intracellular calcium level reached the peak, and decline thereafter up to 72 hours. The patterns of change of the three markers of treatment group were similar to the above. However, the magnitude of changes was relatively lower. A statistically significant difference ( P <0.05) between the ischemia group and treatment group at 6th?12th and 24th after reperfusion was observed. Conclusion Apoptosis may play a vital role in ischemia-reperfusion injury of the retina. bFGF may have a therapeutical effect on ischemia-reperfusion injury by inhibiting the increase of retinal intracellular calcium stores and caspase-3 protein expression.