title: Dopaminergic neurons expressing Fos during waking and paradoxical sleep in the rat.
abstract: Formerly believed to contribute to behavioural waking (W) alone, dopaminergic (DA) neurons are now also known to participate in the regulation of paradoxical sleep (PS or REM) in mammals. Indeed, stimulation of postsynaptic DA1 receptors with agonists induces a reduction in the daily amount of PS. DA neurons in the ventral tegmental area were recently shown to fire in bursts during PS, but nothing is known about the activity of the other DA cell groups in relation to waking or PS. To fulfil this gap, we used a protocol in which rats were maintained in continuous W for 3h in a novel environment, or specifically deprived of PS for 3 days with some of them allowed to recover from this deprivation. A double immunohistochemical labeling with Fos and tyrosine hydroxylase was then performed. DA neurons in the substantia nigra (A9) and ventral tegmental area (A10), and its dorsocaudal extension in the periaqueductal gray (A10dc), almost never showed a Fos-immunoreactive nucleus, regardless of the experimental condition. The caudal hypothalamic (A11) group showed a moderate activation after PS deprivation and novel environment. During PS-recovery, the zona incerta (A13) group contained a significant number and percentage of double-labeled neurons. These results suggest that some DA neurons (A11) could participate in waking and/or the inhibition of PS during PS deprivation whereas others (A13) would be involved in the control of PS.
authors.affiliation: Université de Lyon, Lyon, université Lyon 1, CNRS, UMR5167, Physiologie et physiopathologie du cycle veille-sommeil, F-69008, France. leger@sommeil.univ-lyon1.fr <leger@sommeil.univ-lyon1.fr>
authors.forename: Lucienne
authors.initials: L
authors.lastname: Léger
authors.forename: Emilie
authors.initials: E
authors.lastname: Sapin
authors.forename: Romain
authors.initials: R
authors.lastname: Goutagny
authors.forename: Christelle
authors.initials: C
authors.lastname: Peyron
authors.forename: Denise
authors.initials: D
authors.lastname: Salvert
authors.forename: Patrice
authors.initials: P
authors.lastname: Fort
authors.forename: Pierre-Hervé
authors.initials: PH
authors.lastname: Luppi
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001931:Brain Mapping; D004298:Dopamine / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D009415:Nerve Net / Q000166:cytology / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D012895:Sleep, REM / Q000502:physiology*; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis / Q000378:metabolism; D017557:Ventral Tegmental Area / Q000166:cytology / Q000378:metabolism*; D014851:Wakefulness / Q000502:physiology*
chemical_list: D015415:Biomarkers; D016760:Proto-Oncogene Proteins c-fos; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine