Evidence for Cirdadian Time-Dependent Susceptbility of Blood Pressure to Salt Intake in Normotensive Subjects

本研究的目的是探讨是否有差异的血压反应，盐的摄入量与时间的关系，膳食中添加钠。该研究在7名临床健康的血压正常的女性受试者中进行，在午餐时间和晚餐时间间隔添加三分之二的膳食盐。采用无创自动血压监测仪（ABPM-630）研究了饮食盐转移对血压的影响。在午餐高盐摄入阶段，血压昼夜节律发生了明显的变化。此外，在午餐（显著增加）或晚餐（显著降低）改变盐摄入量时，观察到24小时平均血压水平的不同反应。这些相反的反应证实了这样一种观点，即人类对盐摄入量的紧张易感性是时间依赖于昼夜节律的。应在更广泛的背景下研究盐摄入量向晚餐的转变，以澄清盐摄入的时间是否可用于更好的营养预防或有效的生活方式改变，作为动脉高血压的非药物治疗。

This study is aimed to investigate whether or not there is a differntiated response of blood pressure to salt intake in relation with the time in which dietary sodium added to meals. The study was conducted on 7 clinically healthy normotensive female subjects by adding two-thirds of dietary salt at lunch-time and at dinner-time apart. The blood pressure response to dietary salt shift was studied by means of a non-invasive automated monitoring(ABPM-630). A significant shift of blood pressure circadian rhythm was detected in the stage of high salt intake at lunch-time. Additionally divergent responses in the 24-hour mean level of the blood pressure were observed with shifting salt prevalently at lunch (significant increase) or at dinner (significant decrease). These opposite responses corroborate the view that the tensinogenic susceptibility of human beings to salt intake is time-dependent on a circadian scale. The shift of salt intake to evening meal should be investigated in a broader contex in order to clarify if the timing in salt intake may be exploited for a better nutritional prevention or effective lifestyle modification as the non-pharmacological treatment of arterial hypertension.