低密度脂蛋白胆固醇损伤大鼠离体胰岛的研究  

Study of the damage of low density lipoprotein on isolated pancreatic islets of rats

作　　者：田利民[1] 高翠霞[1] 许衍甲[1] 刘静[1] 

机构地区：[1]甘肃省人民医院内分泌科,兰州730000

出　　处：《中国糖尿病杂志》2008年第4期240-242,共3页Chinese Journal of Diabetes

基　　金：甘肃省自然科学基金暨中青年科技基金资助项目(23031-A25-055-E)

摘　　要：目的研究低密度脂蛋白胆固醇(LDL-C)对体外培养胰岛的损伤作用。方法(1)体外分离培养Wistar大鼠胰岛,并在低糖(2.8mmol/L)和高糖(16.7mmol/L)条件下与不同浓度LDL-C培养,放射免疫法测定胰岛素分泌量;(2)用MTT法检测LDL-C对胰岛活性的影响,用DNA凝胶电泳分析LDL-C对离体胰岛凋亡的影响。结果(1)低糖刺激下,LDL-C对胰岛素分泌无明显影响,但在高糖刺激下,胰岛素分泌水平降低。(2)在LDL-C作用下,胰岛活性显著下降;在较高浓度LDL-C作用下,琼脂糖凝胶电泳图呈典型的细胞凋亡引起的DNA梯状带。结论LDL-C可诱导胰岛凋亡,损伤胰岛功能,降低胰岛素分泌水平,其主要机制可能为氧化损伤。Objective To study the damage of low density lipoprotein （LDL） on the pancreatic islets of rat in vitro. Methods （1）Wistar rat islets of pancreas were isolated for culture and treated with LDL and with low glucose（2.8mmol/L） and high glucose（17.6mmol/L）. Insulin secretions of rat islets stimulated by glucose and LDL were measured by radioimmunoassay. （2）The effect of LDL on the viability of islets was measured by MTT assay. Then the apoptosis of islets treated by LDL was detected by DNA ladder assay. Results （1）No obvious effect of LDL was observed on the islets at low glucose level,while the insulin levels were decreased in rat islets cultured at high glucose. （2）Experiment in vitro showed that LDL can decrease the viability of islets. The apoptosis was detected by DNA ladder assay in cells which had been administered with LDL at high（33mg/L and 66mg/L）concentration. Conclusions An uptake of LDL by islets and subsequent oxidative reactions can result in islets apoptosis, damage the islets function and decrease the insulin secretion.

关 键 词：胰岛 低密度脂蛋白胆固醇 胰岛素分泌 凋亡 

分 类 号：R589[医药卫生—内分泌] R587.1[医药卫生—内科学]