急性高血糖对肱动脉内皮依赖性血管舒张功能影响的研究

Effects of hyperglycemia on changes of endothelium-dependent vasodilation of brachial artery

目的探讨葡萄糖负荷试验所致急性高血糖对血管内皮功能的影响。方法选择正常健康人(NC)、糖耐量减低(IGT)患者和2型糖尿病(T2DM)患者各10例。所有对象均做OGTT,分别于0、60、120min采用高分辨血管外超声检测肱动脉血流介导的内皮依赖性血管舒张功能和硝酸甘油(GNT)介导的内皮非依赖性血管舒张功能。结果IGT组和T2DM组0、60、120min的内皮依赖性血管舒张功能均明显低于NC组(P<0·05)。与0min相比,IGT组和T2DM组60min内皮依赖性血管舒张功能明显降低,120min又回升,明显高于60min者(P<0·05)。IGT组和T2DM组在基础状态下,LDL-C、Lp(a)、FPG、HbA1c与内皮依赖性血管舒张功能呈负相关(P<0·01)。在OGTT中,这两组血糖与内皮依赖性血管舒张功能呈负相关(P<0·001)。结论高血糖快速抑制内皮依赖性血管舒张功能。提示餐后高血糖在糖尿病血管并发症的发生与发展中起重要作用。

Objective To examine whether endothelial dysfunction occurs after 75 g oral glucose loading. Methods Ten healthy men, 10 men with impaired glucose tolerance （IGT）, and 10 men with type 2 DM were selected. All subjects were performed oral glucose tolerant test （OGTT）. Endothelium-dependent arterial dilation and endothelium-independent arterial dilation were measured using high resolution ultrasound technique at 0 rain, 60 rain, and 120 rain during the OGTT. Results During OGTT at 0 min, 60 min, 120 rain, the endothelium-dependent arterial dilation in both IGT and type 2 DM groups were significantly lower than in healthy subjects （all P〈0.05）. Endothelium-dependent arterial dilation in both IGT and type 2 DM groups were significantly lower at 60 min than at 0 min, and also significantly lower at 60 rain than at 120 min （P〈0.05）. At baseline, in IGT and type 2 DM groups, LDL-C,Lp（a）, FPG, HbA1 c were negatively related with endothelium-dependent arterial dilation （all P〈0.01）. During OGTT, blood glucose was negatively related with endotheliumdependent arterial dilation in both IGT and type 2 DM groups （P〈0. 001）. Conclusions Hyperglycemia rapidly suppresses endothelium-dependent arterial dilation. The results strongly suggest that postprandial hyperglycemia may play an important role in the development of diabetic angiopathy.