外源性脑源性神经营养因子对急性高眼压后大鼠视网膜谷氨酸转运体1表达的影响

Effect of exogenous brain-derived neurotrophic factor on the glutamate transporter-1 expression in rat retina following acute ocular hypertension

目的:检测外源性脑源性神经营养因子(BDNF)对急性高眼压后大鼠视网膜谷氨酸转运体1(GLT-1)表达的影响。方法:72只SD大鼠随机分成急性高眼压组、溶媒预处理急性高眼压组和BDNF预处理急性高眼压组,每组动物左眼制作急性高眼压模型,右眼为正常对照,每组动物分别存活1、3、7或14d。用免疫组织化学方法检测外源性BDNF对视网膜GLT-1表达的影响。结果:溶媒预处理急性高眼压组中GLT-1的表达与急性高眼压组相同。与正常视网膜比,急性高眼压组GLT-1的表达在再灌1d时上调,3d时达到高峰,7、14d时表达下调,但仍高于正常对照组。在BDNF预处理急性高眼压组,再灌1d时GLT-1表达明显高于急性高眼压组,3、7、14d时GLT-1表达与急性高眼压组无明显差别。结论:外源性BDNF对急性高眼压后大鼠视网膜的保护作用可能与再灌早期提前上调GLT-1的表达有关。

Objective： To investigate the effect of exogenous brain-derived neurotrophic factor （BDNF） on the glutamate transporter-1 （GLT-1） expression in rat retina following acute ocular hypertension （AOH）. Methods： Seventy two SD rats were randomly divided into three groups： AOH, vehicle pre-treated AOH and BDNF pre-treated AOH. The left eyes of rats in each group were received AOH treatment, and the right eyes served as the normal control. Animals were allowed to survive for 1, 3, 7 and 14 days after reperfusion. Immunohistochemistry for detecting GLT-1 was used. Results： GLT-1 expressions in the vehicle pre-treated AOH and AOH groups were similar. As compared to the normal control, GLT-1 expression in AOH group was markedly increased （P〈0. 05） at the 1st day after reperfusion and reached the highest at the 3rd day. At the 7th and 14th day, the GLT-1 expression was down-regulated, but was still higher than that in the normal control （P〈0. 05）. In addition, GLT-1 expression in the BDNF pre-treated AOH group was significantly higher than that of AOH group at the 1st day after reperfusion （P〈0. 05）. There was no significant difference in GLT-1 expression between AOH group and BDNF pre-treated AOH group at the 3rd, 7th and 14th day. Conclusion： The protection role of BDNF on the rat retina against reperfusion insult after AOH was related to upregulating GLT-1 at the earlier stage of reperfusion.