Brandenberger G, Simon C, Follenius M
Life Sci. 1987 Jun 15;40(24):2325-30. doi: 10.1016/0024-3205(87)90505-4.
During night-sleep, plasma renin activity displays periodic oscillations which are closely related to the alternation of REM-NREM sleep. To see whether this nocturnal rhythm persisted during the day-time, plasma renin activity was measured every 10 min for 24 hours in 4 human volunteers and in 4 others over a 10-h day-time period. To avoid the influence of repeated food intake which stimulates renin release, the subjects were on continuous enteral nutrition. Spectral analyses of the data revealed clear differences between the nocturnal and the diurnal PRA patterns. In subjects on enteral nutrition, sustained 100-min oscillations with strong spectral densities persisted during the night. They were closely related to REM-NREM cycles. During the day-time, however, the fluctuations were damped and less regular, and power spectra were split into 2 or 3 peaks without any predominant period. These results demonstrate that regular 100-min PRA oscillations could only be detected during night-sleep. The clear night-day differences suggest that the underlying oscillatory mechanisms may be weaker during day-time or may be counteracted by other physiological processes.
在夜间睡眠期间，血浆肾素活性呈现周期性振荡，这与快速眼动睡眠（REM）和非快速眼动睡眠（NREM）的交替密切相关。为了观察这种夜间节律在白天是否持续存在，对4名人类志愿者在24小时内每隔10分钟测量一次血浆肾素活性，另外4名志愿者在10小时的白天时间段内进行同样测量。为避免重复进食刺激肾素释放的影响，受试者接受持续肠内营养。数据的频谱分析显示夜间和白天的血浆肾素活性（PRA）模式存在明显差异。在接受肠内营养的受试者中，夜间持续存在具有强频谱密度的100分钟振荡。它们与REM-NREM周期密切相关。然而，在白天，波动受到抑制且不太规则，功率谱分为2个或3个峰值，没有任何主导周期。这些结果表明，只有在夜间睡眠期间才能检测到规律的100分钟PRA振荡。明显的昼夜差异表明，潜在的振荡机制在白天可能较弱，或者可能被其他生理过程抵消。
