晚期糖基化终末产物对糖尿病大鼠主动脉结构和功能的影响

目的探讨晚期糖基化终末产物(AGEs)对主动脉血管结构和功能影响及氨基胍的保护作用。方法将80只雄性SD大鼠随机分为4组:空白对照组(A组),糖尿病组(B组),糖尿病氨基胍干预组(C组)和空白氨基胍干预组(D组),每组20只。药物应用12周观察主动脉功能和结构变化。结果与A组和D组比较,B组、C组主动脉环对去甲肾上腺素引起的收缩反应明显增强,对乙酰胆碱引起的舒张反应则均明显减弱,C组反应强度较B组明显减轻(P0.05,P0.01)。主动脉壁均有AGEs沉积,B组、C组较明显,C组较B组明显减轻(P0.01);超微结构观察显示,A组、D组主动脉内膜大致正常,B组、C组内膜破坏明显,与动脉环结果呈一致性趋势。结论糖尿病大鼠主动脉AGEs含量增多,损伤了主动脉的结构和功能,氨基胍能够减少AGEs的沉积,并对主动脉结构和功能有保护作用。

Effect of advanced glycation end products on aortic structure and function in diabetic rats

Objective To investigate the effect of advanced glycation end products(AGEs) on aortic structure and function in diabetic rats and the protective effect of aminoguanidine.Methods Eighty male SD rats were divided into four groups at random:control group (A) ,diabetic rats group(B) ,diabetic rats with aminoguanidine intervention group(C) and control rats with aminoguanidine intervention group(D) ,each group contained 20 rats.After 12 weeks of drug administration, the changes of aortic stucture and function in different groups were observed.Results Compared with group A and group D,aorta rings showed significantly enhanced contractile response to noradrenaline and significantly attenuated relaxation response to acetylcholine in groups B and C,and group C had a milder response compared with group B (P < 0.05 ,P < 0.01).AGEs accumulated in the aortic endothelium of all groups,groups B and C had more abundant accumulation, group C showed less than group B (P < 0.01).Ultrastructure under electron microscope showed that endothelium was mainly normal in groups A and D,while endothelium in groups B and C was damaged severely,the same trend was found in aortic rings.Conclusions AGEs appears to be abundant in aorta of diabetic rats and damages the structure and function of aorta. Aminoguanidine may prevent the accumulation of AGEs and have a protective effect on aortic structure and function.