Silvani Alessandro
Department of Human and General Physiology, University of Bologna, Bologna, Italy.
Clin Exp Pharmacol Physiol. 2008 Sep;35(9):987-94. doi: 10.1111/j.1440-1681.2008.04985.x. Epub 2008 Jun 28.
Sleep is a heterogeneous behaviour. As a first approximation, it is subdivided objectively into two states: non-rapid eye movement sleep (NREMS) and rapid eye movement sleep (REMS). The mean value and variability of arterial blood pressure (ABP) decrease physiologically from wakefulness to NREMS. In REMS, there may be a further decrease or increase in mean ABP as well as phasic hypertensive events, which enhance the variability of ABP. The reduced mean ABP during NREMS results from a decrease in either heart rate or sympathetic vasoconstrictor tone. During REMS, sympathetic activity to the different cardiovascular effectors undergoes a substantial repatterning. Thus, the mean ABP in REMS reflects a balance between changes in cardiac output and constriction or dilatation of different vascular beds. In both sleep states, the phasic changes in ABP are driven by bursts of vasoconstriction, which may be accompanied by surges of heart rate. The available evidence supports the hypothesis that the sleep-dependent changes in ABP, either tonic or phasic, result from the integration between cardiovascular reflexes and central autonomic commands that are specific to each sleep state.
睡眠是一种异质性行为。初步而言，它可客观地细分为两种状态：非快速眼动睡眠（NREMS）和快速眼动睡眠（REMS）。动脉血压（ABP）的平均值和变异性从清醒状态到NREMS会生理性降低。在REMS中，平均ABP可能会进一步降低或升高，以及出现阶段性高血压事件，这会增加ABP的变异性。NREMS期间平均ABP降低是由于心率或交感缩血管张力降低所致。在REMS期间，对不同心血管效应器的交感神经活动会发生显著的重新模式化。因此，REMS中的平均ABP反映了心输出量变化与不同血管床收缩或扩张之间的平衡。在两种睡眠状态下，ABP的阶段性变化均由血管收缩爆发驱动，这可能伴有心率激增。现有证据支持这样的假说，即ABP的睡眠依赖性变化，无论是持续性还是阶段性的，都是由心血管反射与特定于每种睡眠状态的中枢自主指令之间的整合所致。
