title: Mid-morning tryptophan depletion delays REM sleep onset in healthy subjects.
abstract: Because serotonin is involved in the diachronic regulation of sleep, we tested the effect of a midmorning rapid deficiency in the serotonin precursor tryptophan on the next night's sleep. After a 48-h low-protein diet, 17 healthy volunteers received either a tryptophan-free mixture of amino acids or a placebo at 10:30 A.M., in a randomized double-blind cross-over design, resulting in a 77% decrease and 41% decrease of serum tryptophan at 3:30 P.M. and 9:30 P.M., respectively. Urinary sulfatoxy-melatonin excretion and mood were unaffected by the rapid tryptophan depletion (RTD), but rapid eye movement (REM) sleep latency increased by 21 min (from 91.5 +/- 4.5 min to 112.2 +/- 6.9 min), sleep fragmentation 58%, and REM density of the first REM sleep period doubled. The results show that midmorning RTD delays REM sleep latency during following night-time sleep, whereas evening RTD shortens REM sleep latency in previous studies, and suggest that the serotonin control of REM sleep latency is upregulated.
authors.affiliation: AP-HP, Centre d'Investigation Clinique, Fédération des Pathologies du Sommeil et UPRES EA 2397, Paris, France. isabelle.arnulf@psl.ap-hop-paris.fr
authors.forename: Isabelle
authors.initials: I
authors.lastname: Arnulf
authors.forename: Philippe
authors.initials: P
authors.lastname: Quintin
authors.forename: Jean Claude
authors.initials: JC
authors.lastname: Alvarez
authors.forename: Laurence
authors.initials: L
authors.lastname: Vigil
authors.forename: Yvan
authors.initials: Y
authors.lastname: Touitou
authors.forename: Anne Sophie
authors.initials: AS
authors.lastname: Lèbre
authors.forename: Agnès
authors.initials: A
authors.lastname: Bellenger
authors.forename: Odile
authors.initials: O
authors.lastname: Varoquaux
authors.forename: Jean Philippe
authors.initials: JP
authors.lastname: Derenne
authors.forename: Jean François
authors.initials: JF
authors.lastname: Allilaire
authors.forename: Chawki
authors.initials: C
authors.lastname: Benkelfat
authors.forename: Marion
authors.initials: M
authors.lastname: Leboyer
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002940:Circadian Rhythm / Q000502:physiology; D018592:Cross-Over Studies; D018753:Diet, Protein-Restricted / Q000009:adverse effects / Q000523:psychology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D007319:Sleep Initiation and Maintenance Disorders / Q000097:blood* / Q000523:psychology; D012895:Sleep, REM / Q000502:physiology*; D014364:Tryptophan / Q000097:blood* / Q000172:deficiency*
chemical_list: D014364:Tryptophan