title: Nitric oxide in the regulation of the sleep-wake states.
abstract: Nitric oxide (NO) production involves four different NO-synthases (NOSs) that are either constitutive (neuronal, nNOS; endothelial, eNOS; mitochondrial, mNOS) or inducible (iNOS) in nature. Three main processes regulate NO/NOSs output, i.e., the L-arginine/arginase substrate-competing system, the L-citrulline/arginosuccinate-recycling system and the asymmetric dimethyl-/monomethyl-L-arginine-inhibiting system. In adult animals, nNOS exhibits a dense innervation intermingled with pontine sleep structures. It is well established that the NO/nNOS production makes a key contribution to daily homeostatic sleep (slow-wave sleep, SWS; rapid eye movement sleep, REM sleep). In the basal hypothalamus, the NO/nNOS production further contributes to the REM sleep rebound that takes place after a sleep deprivation (SD). This production may also contribute to the sleep rebound that is associated with an immobilization stress (IS). In adult animals, throughout the SD time-course, an additional NO/iNOS production takes place in neurons. Such production mediates a transitory SD-related SWS rebound. A transitory NO/iNOS production is also part of the immune system. Such a production contributes to the SWS increase that accompanies inflammatory events and is ensured by microglial cells and astrocytes. Finally, with aging, the iNOS expression becomes permanent and the corresponding NO/iNOS production is important to ensure an adequate maintenance of REM sleep and, to a lesser extent, SWS. Despite such maintenance, aged animals, however, are not able to elicit a sleep rebound to deal with the challenge of SD or IS. Sleep regulatory processes in adult animals thus become impaired with age. Reduced iNOS expression during aging may contribute to accelerated senescence, as observed in senescence-accelerated mice (SAMP-8 mice).
authors.affiliation: University of Lyon, Faculty of Medicine, Neurosciences Research Center of Lyon, 8 Avenue Rockefeller, F-69373 Lyon, France. cespuglio@univ-lyon1.fr
authors.forename: Raymond
authors.initials: R
authors.lastname: Cespuglio
authors.forename: Donia
authors.initials: D
authors.lastname: Amrouni
authors.forename: Anne
authors.initials: A
authors.lastname: Meiller
authors.forename: Alain
authors.initials: A
authors.lastname: Buguet
authors.forename: Sabine
authors.initials: S
authors.lastname: Gautier-Sauvigné
mesh_terms: D000818:Animals; D006801:Humans; D053858:Metabolic Networks and Pathways / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology*; D052248:Nitric Oxide Synthase Type I / Q000502:physiology; D052247:Nitric Oxide Synthase Type II / Q000502:physiology; D051381:Rats; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology; D014851:Wakefulness / Q000502:physiology*
chemical_list: D009569:Nitric Oxide; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II