2型糖尿病大鼠不同病程期血管内皮依赖性舒张与内皮素相关

为探讨 2型糖尿病不同病程阶段血管内皮依赖性舒张受损与血浆内皮素之间的关系 ,制备 2型糖尿病大鼠模型 ,利用放射免疫测定法 ,观察大鼠造模 10周与 2 5周时 ,血浆内皮素浓度的变化 ,并利用离体主动脉环舒缩功能实验 ,研究内皮依赖性血管舒张功能损害情况 ,分析两者之间的内在联系。结果发现 ,2型糖尿病大鼠造模 10周时 ,与同龄正常大鼠比较 ,其主动脉内皮依赖性舒张反应明显减弱 ,并伴有血浆内皮素含量升高 ,当造模 2 5周时 ,主动脉内皮依赖性舒张功能进一步受损 ,但血浆内皮素含量不仅不升高 ,反而低于造模 10周的大鼠 (P <0 .0 5 )。结果提示 :2型糖尿病大鼠早期血管内皮依赖性舒张反应减弱可能与内皮素分泌过多有关 ,而晚期血管内皮依赖性舒张反应进一步受损可能与内皮素无关

A Study on the Relationship between Endothelium Dependent Vascular Relaxation and Endothelin at Different Stages of Rats with Non Insulin Dependent Diabetes Mellitus

Aim To investigate the relationship between endothelium dependent vascular relaxation (EDVR) and endothelin at different stages of rats with non-insulin-dependent diabetes mellitus (NIDDM). Methods The rat models of NIDDM were made. At 10 and 25 weeks after injecting STZ, the contents of plasma endothelin were measured respectively with radioimmunoassay, and EDVR actions were studied by isometric tension recording in the isolated aorta rings. Results At 10 weeks of NIDDM rats, the EDVR responses of aortae were obviously weakened and the level of plasma markedly ascended, comparing with normal placebo group. At 25 weeks of NIDDM rats, the EDVR respondes of aortae were further imparired, but the level of plasma endothelin descended and was lower than the NIDDM rats of 10 weeks (P<0.05). Conclusions The results suggest that weakened EDVR may be related to the increased content of endothelin at early stage of NIDDM rat, but impaired EDVR may have nothing to do with endothelin at late period.