A Relationship between Plasma Renin Activity and the Rapid Eye Movement Phase of Sleep in Man*

Abstract
The possible influence of the central nervous system on renin release was investigated by simultaneously monitoring the PRA and the changes of the sleep-wake cycle. Nine normal volunteers were studied, 2 of whom were subjected to an acute sleep reversal procedure. PRA exhibited marked intra- and intersubject variability. No consistent diurnal or ultradian rhythm was observed. The nocturnal variation in PRA, however, was associated with changes in the stage of sleep. The rapid eye movement (REM) phase correlated with a decrease in PRA. In the 9 subjects, 26 measurements were made during REM, all but 2 of which showed a drop compared to the level obtained in the immediately preceding sleep stage (P < 0.001, by two-tailed t test). The mean decrease in PRA accompanying REM was 407 pg/ml-h, and the mean time for PRA to decrease by half after REM onset was 33 min, with a SE of 8 min. The sleep reversal procedure confirmed that REM was associated with decreased PRA even when sleep occurred atan unaccustomed time. REM is demonstrated by these findings to be temporally associatedwith a suppression of PRA. The rate of decrease of PRA after REM onset closely approximates the most recent estimations of PRA half-life, which suggests that REM onset is associated with a virtual cessation in renin production.