高密度脂蛋白对血管内皮依赖性舒张功能的影响

The protective effect of high density lipoprotein on endothelium dependent vasodilatation

目的 探讨血清高密度脂蛋白 胆固醇 (HDL C)水平与肱动脉内皮依赖性舒张功能之间的关系。方法 测定 71例血清总胆固醇水平相对正常的冠心病患者和 34例对照者的血脂水平以及在反应性充血时和含服硝酸甘油后肱动脉的内径变化。结果 冠心病组血流介导的肱动脉舒张和硝酸甘油所致的肱动脉舒张均低于对照组 [分别为 (2 6 1± 2 91) %比 (8 0 1± 4 72 ) %和 (17 2 2± 6 76 ) %比 (2 3 13± 8 6 1) % ,P均 <0 0 0 1]。多因素线性逐步回归分析显示 :血流介导的肱动脉舒张与血清HDL C水平呈正相关 (r=0 32 4,P =0 0 0 2 ) ,与血清总胆固醇、甘油三酯和低密度脂蛋白水平无关 ;硝酸甘油所致的肱动脉舒张也与上述血脂水平无关。根据血流介导的肱动脉舒张程度将两组受试者合并再分为A、B两组 ,A组肱动脉舒张≤ 4% ,B组肱动脉舒张 >4%。结果显示 ,A组HDL C水平明显低于B组 [(1 15± 0 2 6 )mmol/L对 (1 38± 0 5 0 )mmol/L ,P <0 0 1) ]。结论 冠心病患者内皮依赖性及非内皮依赖性的血管舒张功能均受损。HDL C对血管内皮依赖性舒张功能有保护作用 。

Objective The aim of this study was to evaluate the correlation between serum high density lipoprotein cholesterol (HDL C) levels and endothelium dependent dilatation of brachial arteries. Methods Serum lipids and the dilatation changes of brachial arteries during reactive hyperemia and after sublingual glyceryl trinitrate (GTN) were measured in 105 subjects in whom the total cholesteol levels were relatively normal. There were 71 patients with established coronary heart disease and 34 controls. Results Both flow mediated dilatation (FMD) and GTN induced dilatation of brachial arteries in patients with coronary heart disease were much reduced compared with control group (2 61%±2 91% vs 8 01%±4 72% and 17 22%±6 76% vs 23 13%±8 61%, respectively, P< 0 001 for all). Multiple linear stepwise regression analysis showed that FMD of brachial arteries was positively related to HDL C ( r= 0 324, P =0 002). No significant correlation was observed, however, between FMD of brachial arteries and total cholesterol, low density lipoprotein cholesterol or triglycerides and between GTN induced dilatation of brachial arteries and above serum lipids. All subjects were divided into two groups (group A and Group B) acccording to the degree of FMD of brachial arteries. The FMD of brachial arteries was ≤4% in group A and >4% in group B. The serum HDL C level in group A was significantly lower than that in group B (1 15±0 26 mmol/L vs 1 38±0 50 mmol/L, P< 0 01). Conclusion Both endothelium dependent and endothelium independent vasodilatation is impaired in patients with coronary heart disease. HDL C exerts a protective effect on endothelium dependent vasodilatation. The protective effect might contribute to the beneficial effects of HDL C against atherosclerosis.