Lennon-Edwards S, Ramick M G, Matthews E L, Brian M S, Farquhar W B, Edwards D G
Department of Behavioral Health and Nutrition, University of Delaware, Newark, DE, USA; Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA.
Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA.
Nutr Metab Cardiovasc Dis. 2014 Sep;24(9):990-5. doi: 10.1016/j.numecd.2014.05.004. Epub 2014 May 24.
Dietary sodium loading has been shown to adversely impact endothelial function independently of blood pressure (BP). However, it is unknown whether dietary sodium loading impacts endothelial function differently in men as compared to women. The aim of this study was to test the hypothesis that endothelial-dependent dilation (EDD) would be lower in men as compared to women in response to a high sodium diet.
Thirty subjects (14F, 31±2y; 16M, 29±2y) underwent a randomized, crossover, controlled diet study consisting of 7 days of low sodium (LS; 20 mmol/day) and 7 days of high sodium (HS; 300-350 mmol/day). Salt-resistance was determined by a change in 24-hr mean arterial pressure (MAP) ≤ 5 mm Hg between HS and LS as assessed on day 7 of each diet. Blood and 24-hr urine were also collected and EDD was assessed by brachial artery flow-mediated dilation (FMD). By design, MAP was not different between LS and HS conditions and urinary sodium excretion increased on HS diet (P < 0.01). FMD did not differ between men and women on the LS diet (10.2 ± 0.65 vs. 10.7 ± 0.83; P > 0.05) and declined in both men and women on HS (P < 0.001). However, FMD was lower in men as compared to women on HS (5.7 ± 0.5 vs. 8.6 ± 0.86; P < 0.01).
HS reduced FMD in both men and women. In response to an HS diet, FMD was lower in men compared to women suggesting a greater sensitivity of the vasculature to high sodium in men.
已有研究表明，饮食中钠负荷增加会独立于血压（BP）对内皮功能产生不利影响。然而，饮食中钠负荷对男性和女性内皮功能的影响是否存在差异尚不清楚。本研究的目的是检验以下假设：与女性相比，男性在高钠饮食时内皮依赖性舒张（EDD）更低。
30名受试者（14名女性，年龄31±2岁；16名男性，年龄29±2岁）进行了一项随机、交叉、对照饮食研究，包括7天的低钠饮食（LS；20 mmol/天）和7天的高钠饮食（HS；300 - 350 mmol/天）。通过在每种饮食的第7天评估HS和LS之间24小时平均动脉压（MAP）变化≤5 mmHg来确定盐耐受性。同时采集血液和24小时尿液样本，并通过肱动脉血流介导的舒张（FMD）评估EDD。根据设计，LS和HS条件下MAP无差异，且HS饮食时尿钠排泄增加（P < 0.01）。LS饮食时男性和女性的FMD无差异（10.2 ± 0.65 vs. 10.7 ± 0.83；P > 0.05），HS饮食时男性和女性的FMD均下降（P < 0.001）。然而，HS饮食时男性的FMD低于女性（5.7 ± 0.5 vs. 8.6 ± 0.86；P < 0.01）。
HS饮食降低了男性和女性的FMD。在HS饮食时，男性的FMD低于女性，提示男性血管系统对高钠更敏感。
