摘要
目的观察胰岛素抵抗(IR)和2型糖尿病大鼠胸主动脉内皮依赖性舒张功能和一氧化氮(NO)的变化,探讨IR和高血糖状态下内皮功能障碍的发生机制。方法4～6周龄雄性SD大鼠高糖高脂喂养6周,建立IR模型(IR组),再从中取20只予小剂量链脲佐菌素(STZ)腹腔注射建立2型糖尿病大鼠模型(DM组),并用正常葡萄糖高胰岛素钳夹技术的葡萄糖输注率(GIR)评价IR。观察大鼠离体主动脉对乙酰胆碱依赖性血管舒张功能和NO含量的变化,同时检测空腹血糖(FPG)、空腹胰岛素(FINS)、甘油三酯(TG)和胆固醇(TC)水平。结果IR组和DM组体重、FINS、TG和TC均显著高于正常对照组(NC组)(P<0.01),DM组FPG显著高于NC组和IR组(P<0.01);IR组和DM组的GIR均显著低于NC组(P<0.01),但IR组和DM组GIR无显著差异。IR和DM组大鼠胸主动脉对乙酰胆碱诱导的内皮依赖性舒张功能和NO含量均显著低于NC组(P<0.05和P<0.01),且DM组上述指标又低于IR组(P<0.05)。大鼠主动脉对乙酰胆碱诱导的最大舒张反应与FPG、TG、TC和FINS呈显著负相关(r-0.637,-0.622,-0.663,-0.645,均P<0.01)。结论IR和2型糖尿病大鼠主动脉内皮依赖性舒张功能和NO水平显著下降,且DM组比IR组下降更显著,表明高血糖和IR是内皮功能障碍的重要影响因素。
Objective To observe the change of endothelium - dependent vasodilation function of aorta and nitric oxide （NO） level in insulin - resistant rats （ IR group） and type 2 diabetic rats （ DM group）, and to explore the mechanism of endothelial dysfunction in the state of IR and hyperglicaemia. Methods IR rat model was establish 4 - 6 weed old male SD rats by high glucose and high fat feeding for 6 weeks. Type 2 diabetic rat model was establish by intraperitoneal injection of low dose streptozotocin （STZ）. IR was evaluated by glucose infusion rate（GIR） of euglycemic hyperinsulinemic clamp technique. Achtylcholine（Ach） - dependent vasodilation response and NO level were observed in isolated aorta of rats. Body weight, fast plasma glucose （ FPG）, fast insulin （ FINS ）, Triglyeride （TG） and cholesteol （ TC ） were measured in all rats. Results Body weight,FINS,TG and TC were higher in IR and DM group than those in normal control group （NC group）（P 〈 0. 01 ） while FPG in DM group was higher than that in NC and IR group（ P 〈 0.01 ）. GIR was significantly lower in IR and DM group compared with that in NC a group（P 〈0.01 ） ,but there was no significant difference be- tween in IR and DM group. Ach - dependent vasodilation response and NO level of isolated aorta significantly decreased in IR and DM group（ P 〈 0.05 and P 〈 0.01 ） , and those indexs were singnificantly lower in the latter compared with those in the former. There was a significant negative correlation between the the maximum Ach - dependent vasodilation response of isolated aorta and FPG,TG,TC ,FINS（r= -0. 637, -0. 622, -0. 663, -0. 645,All P〈0. 01）. Conclusions The Ach - dependent vasodilation response and NO level of isolated aorta decreased in IR and type 2 diabetic rats, With more prominent changes in the latter. Hyperglicaemia and insulin - resistance are important influencing factors of endothelial dysfunction.
出处
《广东医学》
CAS
CSCD
北大核心
2007年第11期1733-1736,共4页
Guangdong Medical Journal
基金
湖南省科技厅发展基金资助项目(编号:06sk3023)
关键词
胰岛素抵抗
糖尿病
2型
正常葡萄糖高胰岛素钳夹技术
内皮依赖性舒张功能
Insulin resistance Type 2 diabetes mellitus Euglycemic hyperinsulinemic clamp technique Endothelium - dependent vasodilatation
