title: Differential effects of sodium oxybate and baclofen on EEG, sleep, neurobehavioral performance, and memory.
abstract: OBJECTIVE
  Sodium oxybate (SO) is a GABAβ agonist used to treat the sleep disorder narcolepsy. SO was shown to increase slow wave sleep (SWS) and EEG delta power (0.75-4.5 Hz), both indexes of NREM sleep (NREMS) intensity and depth, suggesting that SO enhances recuperative function of NREM. We investigated whether SO induces physiological deep sleep.
  
  
  METHODS
  SO was administered before an afternoon nap or before the subsequent experimental night in 13 healthy volunteers. The effects of SO were compared to baclofen (BAC), another GABAβ receptor agonist, to assess the role of GABAβ receptors in the SO response.
  
  
  RESULTS
  As expected, a nap significantly decreased sleep need and intensity the subsequent night. Both drugs reversed this nap effect on the subsequent night by decreasing sleep latency and increasing total sleep time, SWS during the first NREMS episode, and EEG delta and theta (0.75-7.25 Hz) power during NREMS. The SO-induced increase in EEG delta and theta power was, however, not specific to NREMS and was also observed during REM sleep (REMS) and wakefulness. Moreover, the high levels of delta power during a nap following SO administration did not affect delta power the following night. SO and BAC taken before the nap did not improve subsequent psychomotor performance and subjective alertness, or memory consolidation. Finally, SO and BAC strongly promoted the appearance of sleep onset REM periods.
  
  
  CONCLUSIONS
  The SO-induced EEG slow waves seem not to be functionally similar to physiological slow waves. Our findings also suggest a role for GABAβ receptors in REMS generation.
authors.affiliation: Center for Integrative Genomics (CIG), University of Lausanne, Lausanne, Switzerland.
authors.forename: Julie
authors.initials: J
authors.lastname: Vienne
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Lecciso
authors.forename: Irina
authors.initials: I
authors.lastname: Constantinescu
authors.forename: Sophie
authors.initials: S
authors.lastname: Schwartz
authors.forename: Paul
authors.initials: P
authors.lastname: Franken
authors.forename: Raphaël
authors.initials: R
authors.lastname: Heinzer
authors.forename: Mehdi
authors.initials: M
authors.lastname: Tafti
mesh_terms: D000328:Adult; D001418:Baclofen / Q000494:pharmacology*; D004569:Electroencephalography; D058786:GABA-B Receptor Agonists / Q000494:pharmacology; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D017286:Polysomnography; D011597:Psychomotor Performance / Q000187:drug effects; D018080:Receptors, GABA-B / Q000378:metabolism; D012890:Sleep / Q000187:drug effects* / Q000502:physiology; D012894:Sleep Stages / Q000187:drug effects / Q000502:physiology; D012978:Sodium Oxybate / Q000494:pharmacology*; D013997:Time Factors; D014851:Wakefulness / Q000187:drug effects / Q000502:physiology; D055815:Young Adult
chemical_list: D058786:GABA-B Receptor Agonists; D018080:Receptors, GABA-B; D012978:Sodium Oxybate; D001418:Baclofen