平滑肌钙激活钾通道表达转换参与糖尿病大鼠动脉粥样硬化发生  

Ca^(2+)-activated K^+ channel switching in smooth muscle participates in atherosclerosis development in diabetic rats

作　　者：王燕[1] 赵丽梅[1] 苏兴利[2] 于玮[2] 邓秀玲[1] 

机构地区：[1]西安交通大学医学院生理学与病理生理学系,陕西西安710061 [2]西安医学院生理学与病理生理学教研室,陕西西安710021

出　　处：《南方医科大学学报》2014年第2期188-192,共5页Journal of Southern Medical University

基　　金：国家自然科学基金(81070129;81170137)~~

摘　　要：目的观察糖尿病大鼠胸主动脉组织形态学及平滑肌钙激活钾通道(Ca2+-activated K+channels,KCa)表达的变化。方法采用高糖高脂饲料喂养SD大鼠8周和链脲佐菌素腹腔注射(30 mg/kg)建立实验性糖尿病大鼠模型,检测血液生化指标,进行胸主动脉HE、弹力纤维、Masson染色和抗平滑肌α-actin免疫组织化学染色,并采用逆转录聚合酶链反应和免疫印迹技术观察主动脉平滑肌KCa通道表达的变化。结果与年龄匹配的对照组大鼠相比,模型大鼠体质量下降,血糖、血脂、糖化血红蛋白和平均血压明显升高,并出现多食、多饮、多尿等典型糖尿病体征;主动脉组织学出现早期粥样硬化变化,表现为内皮受损不完整,表面有炎细胞粘附,内膜下平滑肌细胞排列紊乱,局部增生,弹力纤维中断、融合,胶原纤维增多等;主动脉中层平滑肌KCa1.1α亚单位和β亚单位表达降低,KCa3.1表达明显增加。结论平滑肌KCa表达转换参与糖尿病动脉粥样硬化的发生。Objective To investigate the changes in aorta morphology and Ca2＋-activated K＋ （KCa） channel expression in the diabetic rats. Methods A diabetic rat model was established by a single intraperitoneal injection of streptozotocin （30 mg/kg） after a modified high fat and glucose diet for 8 weeks. Pathological changes in the aorta were observed with HE staining, elastic fiber staining, Masson＆#39;s trichrome staining and immunohistochemistry. Both the mRNA and protein levels of KCa channels in the aorta were measured by RT-PCR and Western blotting. Results Early atherosclerotic changes were observed in the aorta wall of the diabetic rats. The mRNA and protein levels of KCa1.1 channel α- and β-subunits were significantly decreased, while the expression of KCa3.1 channels was obviously enhanced in the middle layer of the aorta in the diabetic rats. Conclusion KCa channel switching in smooth muscles may play a role in the development of atherosclerosis in diabetic rats.

关 键 词：糖尿病 血管平滑肌 钙激活钾通道 动脉粥样硬化 

分 类 号：R587.1[医药卫生—内分泌]