Aldosterone release during the sleep-wake cycle in humans

The aim of this study was to assess the relative influence on the 24-h aldo sterone profile of the adrenocorticotropic system, primarily modulated by a circadian rhythmicity, and the renin-angiotensin system, which is influenc ed by sleep. Cortisol, plasma renin activity (PRA), and aldosterone were me asured far 24 h in healthy subjects under basal conditions, once with noctu rnal sleep and once with a night of sleep deprivation followed by 8 h of da ytime sleep. The sleep period displayed high mean aldosterone levels, pulse amplitude, and frequency that were reduced during waking periods. During s leep, aldosterone pulses were mainly related to PRA oscillations, whereas t hey were mainly associated with cortisol pulses during waking periods. Cros s-correlation analysis between sleep electroencephalographic activity in th e delta band and aldosterone levels yielded significant results, aldosteron e following delta waves by similar to 30 min. This study demonstrates that the 24-h aldosterone profile is strongly influenced by sleep processes. A d ual influence, by the renin-angiotensin system during sleep and by the adre nocorticotropic system during wakefulness, is exerted on aldosterone pulses throughout the 24-h period.