Changes of sleep related renin secretion after sleep deprivation in humans

Sleep is a time of maximal renin secretion during 24 hours (1). Renin is the one hormone with the most distinct ties to the non-rapid-eye-movement (NREM)-rapid-eye-movement (REM)-sleep cycle. During NREM sleep PRA increases, whereas it decreases during REM sleep. Increases of PRA are linked increases of/with slow wave activity (SWA), whereas decreases of PRA are linked with decreases of SWA. The most powerful method to stimulate slow wave sleep (SWS) and SWA is sleep deprivation. The effect of sleep deprivation on the sleep related renin secretion is unknown. We compared sleep EEG and plasma renin levels between nights before and after 40 hours of sleep deprivation in 48 healthy volunteers (24 women and 24 men) with a mean age 42±2.93 resp 37±2.80 of years (ranging from 19 to 69; male subjects:19–64; female subjects:22–69). During the baseline night and the recovery night an indwelling intravenous catheter was inserted for blood collection every 30min between 2000 and 2300 and every 20min between 2200 and 0700. During the recovery night subjects received in randomized fashion repetitive injections of either growth hormone-releasing hormone (GHRH) or corticotropin-releasing-hormone (CRH) or placebo. It is well established that a reciprocal interaction of the sleep promoting GHRH and the sleep impairing CHR play the key role in sleep regulation. We focus on the differences in renin secretion between baseline and recovery nights.

The pattern of renin secretion with oscillations of renin concentrations strictly related to the NREM-REM-cycle persisted after sleep deprivation. But the concentration levels were significantly affected after sleep deprivation [Wilks multivariate tests of significance; effect of sleep deprivation: F=3.91, sig of=0.049], and this effect was remarkable on both mean location and delta values (univariate F-tests; p<0.05). Renin mean concentration and renin delta increased significantly after sleep deprivation, indicating higher renin levels and a higher amplitude of renin secretion during the recovery night This effect did not differ between women and men. No differences between the treatments GHRH, CRH and placebo on renin levels after sleep deprivation were found. When the two halves of the night were investigated separately, a higher effect of sleep deprivation on renin variables was shown during the first half of the night. During the 1^st night half the delta renin value differed between women and men with a significantly higher value in males than in females. This study supports the view of a distinct link between PRA and sleep.

Supported by a grant from the Deutsche Forschungsgemeinschaft (YA12/1–1 1–2)

References:

1. Brandenberger, G et al, 1994. Renin as a biological marker of the NREM-REM sleep cycle: effect of REM sleep suppression. J. Sleep Res. 3, 30–35.