糖耐量减低患者血小板活化和血管内皮功能的变化

Changes of Platelet Activation and Vascular Endothelial Function in Patients with Impaired Glucose Tolerance

为观察糖耐量减低对血小板活化和血管内皮功能的影响 ,选择 40例糖耐量减低患者 ,测定血小板α 颗粒膜蛋白浓度 ,并应用高分辨超声测量右肱动脉在静息时 (基础内径 )、反应性充血 (流量介导血管舒张 )、舌下含服硝酸甘油 (硝酸甘油介导血管舒张 )时的舒张期内径。取 30例查体健康者作对照组。结果发现 ,糖耐量减低组空腹血糖与对照组无显著差异 (P >0 .0 5 ) ,而空腹时血小板α 颗粒膜蛋白较对照组显著升高 (P <0 .0 1) ,流量介导血管舒张时内径较对照组显著降低 (P <0 .0 1) ,而两组间硝酸甘油介导血管舒张内径和基础内径无显著差异 (P >0 .0 5 )。口服 75g葡萄糖负荷后 2h ,糖耐量减低组血糖浓度显著高于对照组 ,血小板α 颗粒膜蛋白较空腹状态时显著升高 (P <0 .0 1) ,同时 2h流量介导血管舒张时内径较空腹时进一步降低 ,差异显著 (P <0 .0 1)。相关分析表明 ,糖耐量减低组空腹血糖与血小板α 颗粒膜蛋白和流量介导血管舒张时内径无显著相关 ,而糖负荷后 ,血糖变化程度与血小板α 颗粒膜蛋白变化程度显著正相关 (P <0 .0 1) ,与流量介导血管舒张时内径的变化程度显著负相关 (P<0 .0 1)。血小板α 颗粒膜蛋白水平与流量介导血管舒张时内径显著负相关 (P <0 .0 1)。

Aim To investigate the changes of platelet activation and vascular endothelial function in patients with impaired glucose tolerance (IGT). Methods 40 patients with IGT were chosen and the level of platelet alpha granule membrane protein (GMP-140) was measured in these patients. Meanwhile, flow-mediated endothelium dependent dilation of branchial arteries was observed with high resolution ultrasound by celermajer's method. The diameter of branchial arteries were respectively measured at rest (basal diameter, BD), during reactive hyperemia (increased flow causing endothelium-dependent dilation, FMD) and after sublingual nitroglycerine (nitroglycerine causing endothelium-independent dilation, NCD). Data of 30 healthy persons were taken as the control group. Results There was no significant difference in the level of fasting blood glucose (FBG) between the control group and the IGT group. However, after 75 g oral glucose loading for 2 h, the level of blood glucose (2hBG) in the IGT group was higher than that in the control group. In the fasting state, the level of FMD was significantly reduced and the level of platelet GMP-140 was significantly increased in the IGT group as compared with those in the control group. After 75 g oral glucose loading, the level of FMD (2hFMD) was lower than that in the fasting state and the level of platelet GMP-140 (2hGMP-140) was higher than those in the fasting state. Linear correlation analysis showed that there was no significant relation between FBG and the levels of GMP-140 and FMD. However, before and after oral glucose loading, the changes of blood glucose [△(2hBG-FBG)] were positively correlated with the changes of platelet GMP-140 [△(2hGMP-140-GMP-140)], and the changes of blood glucose [△(2hBG-FBG)] were negatively correlated with the changes of FMD [△(2hFMD-FDM)]. The level of platelet GMP-140 was negatively correlated with the level of FMD. Conclusion Platelet activation was increased and vascular endothelial function was impaired in the patients with IGT, and oral glucose loading aggravate the increasing platelet activation and the endothelial dysfunction.