方法：SD大鼠60只，随机分为对照组(CON)及糖尿病组(DM)，糖尿病组一次性腹腔注射1% STZ诱发糖尿病鼠模型，两组于第4，8，12wk分别行HE、透射电镜及TUNEL法检测RGCs的凋亡情况，并应用激光共聚焦显微镜检测RGCs内钙离子浓度的变化。

结果：糖尿病组第8wk开始出现RGCs数量减少、细胞排列紊乱的病理改变，第12wk更为明显。糖尿病组透射电镜下可见第4wk时RGCs出现线粒体肿胀； 第8wk时RGCs内肿胀的线粒体更为明显、数目增多，染色质边集于核膜周边，部分细胞体积缩小、细胞器减少； 第12wk时出现RGCs体积变小，甚至出现细胞核断裂。TUNEL阳性RGCs最早于糖尿病组第4wk时出现，随病程延长凋亡的阳性细胞逐渐增多，凋亡指数与同期对照组相比，差异有统计学意义(P<0.01)。糖尿病组第8，12wk时RGCs内钙离子浓度明显高于同期对照组，差异显著(P<0.01)； 糖尿病组第8wk与第12wk比较，升高差异亦有统计学意义(P<0.05)。

结论：糖尿病早期出现了视网膜神经节细胞的凋亡，其机制可能与细胞内钙离子浓度升高有关。

METHODS: Sixty SD rats were randomly divided into two groups: control group(CON)and diabetes mellitus group(DM). Diabetic rat model was produced by intraperitoneal injection of 1% STZ in 30 adult male SD rats. At 4, 8, 12wk,the rats were killed and eyeballs were enucleated for the HE staining, TUNEL staining, transmission electron microscopy detection respectively, and laser confocal microscope detection was used to detect the calcium ion concentration.

RESULTS:At 8wk RGCs decreased gradually and appeared disordered arrangement and got worse at 12wk in DM group. In DM group, mitochondrial swelling was detected at 4wk., and became more obvious, more in number at 8wk with reduction in some cells' volume and the number of organelles decreased. In DM group, few TUNEL positive RGCs were seen at 4wk, and became more and more at 8 and 12wk. The apoptosis index was significantly higher in DM group compared with CON group in different time points(P<0.01). Intracellular calcium ion concentration of RGCs in DM group began to elevate obviously at 8 and 12wk in contrast with CON group in the same time point(P<0.01). In DM group, Intracellular calcium ion concentration of RGCs increased difference was statistically significant between 8 and 12wk(P<0.05).

CONCLUSION: The study suggested that RGCs apoptosis occurs in early stage of diabetes, the mechanism might be associated with increased intracellular calcium ion concentration.