摘要
目的:观察糖尿病早期大鼠,视网膜神经细胞凋亡与caspase-3表达变化的关系。方法:健康雄性8周龄SD大鼠36只,建立糖尿病大鼠模型18只,正常对照18只。再各自分为4,8,12wk3组,每组6只大鼠。TdT介导DNA缺口末端的dUTP标记(TUNEL)法检测视网膜神经细胞的凋亡程度;免疫组织化学方法检测半胱氨酸天冬氨酸蛋白酶3(caspase-3)蛋白表达水平,实时荧光定量聚合酶链反应(PCR)法检测caspase-3mRNA表达情况。结果:正常对照组4,8,12wk大鼠均未见视网膜神经细胞凋亡。糖尿病组大鼠于建模后4wk即出现视网膜神经细胞凋亡,8wk和12wk大鼠视网膜神经凋亡程度较同期正常对照组大鼠均明显增强。神经细胞凋亡主要位于视网膜神经节细胞层及内核层。正常对照组4,8,12wk大鼠视网膜均未见caspase-3蛋白阳性表达,糖尿病组大鼠4wk即可见caspase-3蛋白阳性表达,8和12wk时表达增强。正常对照组4,8,12wk大鼠caspase-3mRNA表达RQ值分别为1.6±0.6,1.5±0.5,1.6±0.3;糖尿病组4,8,12wk大鼠caspase-3mRNA表达RQ值分别为5.7±1.2,12.6±2.3,14.3±2.1;较同期对照组均明显升高,差异有统计学意义(P<0.05)。结论:糖尿病早期视网膜神经细胞凋亡可能与capase-3表达增强有关。
AIM： To probe the relationship between the apoptosis of diabetic rats retinal neurons and change of caspase-3 expression in early diabetic rats. METHODS： Eighteen male 8-week-aged SD rats were injected with a single dose of streptozotocin （60mg/kg） to induce the diabetic model, and then they were divided into 3 groups at 4, 8 and 12 weeks （each group, n=6）. Another 18 male 8-week-aged SD rats were the normal control group, and were raised at the same time without any intervertion, also divided into 3 groups at 4, 8 and 12 weeks （each group, n=6）. Apoptosis of retinal neurons was detected by TdT-mediated dUTP nick end label （TUNEL） assay. The protein expression of caspase-3 was detected by immunohistochemistry. Caspase-3 mRNA levels were determined by SYBR Green Realtime PCR Master Mix.
RESULTS： There were no apoptosis neurons in control groups retina at 4, 8, 12 weeks. Apoptosis of the retinal neurons occurred 4 weeks after the onset of diabetes, and the apoptosis degrees were significantly higher than that of age-matched control groups at 8 and 12 weeks. The apoptosis of the retinal neurons located in the rentinal ganglion cells layer （GCL） and the inner nuclear layer （INL）. Caspase-3 protein expression was not observed in the control rats retina at 4, 8, 12 weeks. Positive staining of caspase-3 occurred 4 weeks after the onset of diabetes, and enhanced at 8 and 12 weeks. In control rats at 4, 8 and 12 weeks, caspase-3 mRNA levels were 1.6±0.6, 1.5±0.5, 16±0.3 respectively. Caspase-3 mRNA levels in diabetic rats that had diabetes for 4, 8 and 12 weeks were 5.7±1.2, 12.6±2.3, 14.3±2.1 respectively, which were greater than that in the control groups （P〈0.05）.
CONCLUSION： The apoptosis of the retinal neurons in diabetic rats may be related with the enhance of the caspase-3 expression.
出处
《国际眼科杂志》
CAS
2010年第5期847-849,共3页
International Eye Science
