Aging and interaction of natriuretic factors on renal and vascular sodium pump

一项随机、安慰剂对照和交叉设计的研究探讨了在5周低钠饮食条件下MBG排泄与收缩压和主动脉脉搏波速度之间的关系。（77 9mmol/d）和5周的正常钠（144 +/- 7 mmol/d）中年/老年患者的饮食（8名男性和3名女性; 60 ± 2岁），血压中度升高（139 ± 2 / 83 ± 2 mm Hg）。 低钠组与正常组相比，尿MBG排泄量（每周测量; 25.4 +/- 1.8 vs. 30.7 +/- 2.1 pmol/kg/天）、收缩压（127 +/- 3 vs. 138 +/- 5 mmHg）和主动脉脉搏波速度（700 +/- 40 vs. 843 +/- 36 cm/s）均较低（均P<0.05）。在所有周内，尿MBG水平与收缩压（斜率=0.61，P<0.001）和钠排泄（斜率=0.46，P<0.001）相关。这些关联在正常情况下持续存在，但在低钠情况下则不存在（均P<0.005）。MBG排泄还与主动脉脉搏波速度（斜率=0.70，P=0.02）和内皮细胞NAD（P）H氧化酶-p47 phox表达（斜率=0.64，P=0.006）相关。 这些结果首次表明，在人类中，饮食钠限制降低尿MBG水平，尿MBG排泄与收缩压、主动脉僵硬度（主动脉脉搏波速度）和氧化酶NAD（P）H氧化酶的内皮细胞表达呈正相关。重要的是，在美国饮食典型的钠摄入量范围内，MBG排泄与收缩压和主动脉僵硬度呈正相关，这是心血管衰老的主要特征。

Randomized, placebo-controlled, and crossover design study explored the associations among MBG excretion with systolic BP and aortic pulse-wave velocity across conditions of 5 weeks of a low-sodium (77 9 mmol/d) and 5 weeks of a normal-sodium (144 +/- 7 mmol/d) diet in middle aged/older patients (eight men and three women; 60 +/- 2 years) with moderately elevated blood pressure (139 +/- 2 / 83 +/- 2 mm Hg). Urinary MBG excretion (weekly measurements; 25.4 +/- 1.8 vs. 30.7 +/- 2.1 pmol/kg per day), systolic BP (127 +/- 3 vs. 138 +/- 5 mmHg), and aortic pulse-wave velocity (700 +/- 40 versus 843 +/- 36 cm/s) were lower during the low- versus normal-sodium condition (all P<0.05). Across all weeks, urinary MBG levels were related to systolic BP (slope=0.61, P<0.001) and sodium excretion (slope=0.46, P<0.001). These associations persisted during the normal- but not the low-sodium condition (both P<0.005). MBG excretion also was associated with aortic pulse-wave velocity (slope=0.70, P=0.02) and endothelial cell expression of NAD(P)H oxidase-p47phox (slope=0.64, P=0.006). These results show, for the first time in humans, that dietary sodium restriction reduces urinary MBG levels and that urinary MBG excretion is positively associated with systolic BP, aortic stiffness (aortic pulse-wave velocity), and endothelial cell expression of the oxidant enzyme NAD(P)H oxidase. Importantly, MBG excretion is positively related to systolic BP and aortic stiffness, a major feature of cardiovascular aging, over ranges of sodium intake typical of an American diet.