Melatonin and s-20098 increase rem sleep and wake-up propensity
without modifying nrem-sleep homeostasis.
Cajochen, Christian, Kurt Kr[umlaut]auchi, David M[diaeresis]ori,
Peter Graw, and Anna Wirz-Justice.
Psychiatric University Clinic, CH-4025 Basel, Switzerland
APStracts 3:0395R, 1996.
The pineal hormone melatonin has been implicated in the circadian
regulation of sleep. In a cross-over design, we investigated the
effect of acute administration of 5mg melatonin and a melatonin
agonist (S-20098, 5 and 100mg) in healthy young men, when given 5
hours before bedtime, on sleep structure and electroencephalogram
(EEG) power density. Each trial comprised a baseline, a treatment and
a post-treatment sleep episode. Relative to the placebo condition,
all treatments phase advanced the core body temperature rhythm
[24,25]. Rapid-eye-movement (REM) sleep was increased after both
melatonin and S-20098. This increase in REM sleep was most pronounced
in the first REM sleep episode. On the post-treatment night after
melatonin and S-20098 administration, more wakefulness was present in
the latter half of the sleep episode. EEG power density between 0.25
-20 Hz during either non rapid-eye-movement (NREM) or REM sleep did
not differ from placebo. Thus, a single early evening dose of
melatonin or the agonist S-20098 increases REM sleep propensity and
advances sleep termination while at the same time the EEG in NREM
sleep remains unaffected.
Received 17 November 1995; accepted in final form 16 October
1996.
APS Manuscript Number R723-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996