碱性成纤维细胞生长因子对N-甲基-D-天冬氨酸诱导大鼠视网膜神经节细胞层损伤的保护作用

Neuroprotective effect of basic fibroblast growth factor on N-methyl-D-aspartate-induced injury of rat retinal ganglion cells

目的探讨玻璃体腔内注射碱性成纤维细胞生长因子(bFGF)对N-甲基-D-天冬氨酸(NMDA)诱导大鼠视网膜神经节细胞层损伤的保护作用。方法将健康雄性Wistar大鼠随机分入3组:空白对照组大鼠予玻璃体腔内注射磷酸盐缓冲液(PBS)4L,NMDA组大鼠予玻璃体腔内注射溶有100nmol NMDA的PBS4L,NMDA+bFGF组大鼠予玻璃体腔内注射溶有100nmol NMDA+20g bFGF的PBS 4L。注射24h后取视网膜组织切片行原位末端标记法(TUNEL)染色,观察细胞的凋亡率;提取视网膜蛋白质,采用Western印迹法检测B细胞淋巴瘤/白血病-2(Bcl-2)和Bcl-2相关X蛋白(Bax)的蛋白含量。注射7d后取视网膜组织切片行苏木精-伊红(H-E)染色,观察细胞的存活率。结果 NMDA组和NMDA+bFGF组的细胞凋亡率分别为(62.2±1.9)%和(43.3±1.9)%,均显著高于空白对照组的(2.4±1.6)%(P值均<0.01),NMDA+bFGF组的细胞凋亡率显著低于NMDA组(P<0.01)。NMDA组和NMDA+bFGF组的细胞存活率分别为(37.9±7.9)%和(66.7±6.1)%,均显著低于空白对照组的(96.0±3.4)%(P值均<0.01),NMDA+bFGF组的细胞存活率显著高于NMDA组(P<0.01)。NMDA组和NMDA+bFGF组的Bcl-2/Bax比值分别为0.3±0.1和0.6±0.1,均显著低于空白对照组的0.8±0.1(P值均<0.01),NMDA+bFGF组的Bcl-2/Bax比值显著高于NMDA组(P<0.01)。结论 bFGF能逆转NMDA对视网膜神经节细胞层的损伤作用,起到有效的神经保护作用。

Objective To explore the neuroprotective effect of basic fibroblast growth factor （bFGF） on a model of N-methyI-D-aspartate （NMDA）-induced injury of rat retinal ganglion cells. Methods Healthy male Wistar rats were divided into three groups. In control group, phosphate buffered solution （4 L） was injected into the vitreous body. In NMDA group, 4 L phosphate buffered solution containing 100 nmol NMDA was injected into the vitreous body. In NMDA plus bFGF group, 4 L phosphate buffered solution containing 100 nmol NMDA and 20 g bFGF were injected into the vitreous body. Twenty-four hours after injection, apoptotic rate was observed through TdT-mediated dUTP nick and labeling （TUNEL）, and protein levels of B-cell lymphoma-2 （Bcl-2） and Bcl-2 associated X protein （Bax） were measured by Western-blot. Seven days after injection, H-E staining was used to observe the survival rate of rat retina. Results The apoptotic rate in NMDA group （E62.2 ± 1.9] % ） and NMDA plus bFGF group （[43.3±1.91% ） were significantly higher than that in the control group （[2.4± 1.6] %, both P〈0.01）, while the apoptotic rate in the NMDA plus bFGF group was significantly lower than that in the NMDA group （P 〈 0.01）. The cell survival rate in the NMDA group （[37.9 ± 7.91% ） and NMDA plus bFGF group （[66.7 ±6.1]%） were significantly lower than that in the control group （[96.0±3.4]%, both P〈0.01）, while the cell survival rate in the NMDA plus bFGF group was significantly higher than that in the NMDA group （P〈 0.01 ）. The ratio of Bcl-2 to Bax in the NMDA group （0.3 ± 0.1 ） and NMDA plus bFGF group （0.6 ± 0. 1 ） were significantly lower than that in the control group （0.8 ± 0. 1, both P〈0.01 ）, while the ratio in the NMDA plus bFGF group was significantly higher than that in the NMDA group （P 〈 0. 01 ）. Conclusion bFGF has a neuroprotective effect on rat retinal ganglion cells injured by NMDA.