CEREBROSPINAL FLUID (CSF) EXTRACTED IMMEDIATELY AFTER REM-SLEEP DEPRIVATION PREVENTS REM REBOUND AND CONTAINS VASOACTIVE-INTESTINAL-PEPTIDE(VIP)

Intraventricular administration of cerebrospinal fluid (CSF) obtained from sleep deprived (SD) animals and vasoactive intestinal peptide (VI P) have been shown to increase rapid eye movement (REM) sleep. It has thus been suggested that VIP may accumulate in the CSF as a consequenc e of waking, and might thus be partly responsible for the subsequent r ebound of REM sleep which follows prolonged wakefulness. To this date there are no studies testing this hypothesis. The purpose of this stud y, therefore, was to determine REM rebound following the extraction of CSF immediately after REMSD and to quantify by radioimmunoassay (RIA) the concentration of VIP in the CSF of progressively increasing REMSD periods. The results showed that REM rebound normally seen following REMSD is reduced by extraction of CSF, and that VIP concentration in s uch CSF is augmented. The results are discussed in terms of the possib ility that waking induces an accumulation of VIP in the CSF, which is in turn involved in the production of REM sleep.