title: c-Fos expression in dopaminergic and GABAergic neurons of the ventral mesencephalic tegmentum after paradoxical sleep deprivation and recovery.
abstract: Evidence suggests that dopaminergic neurons of the ventral mesencephalic tegmentum (VMT) could be important for paradoxical sleep (PS). Here, we examined whether dopamine (DA) and adjacent gamma-aminobutyric acid (GABA)-synthesizing neurons are active in association with PS recovery as compared to PS deprivation or control conditions in different groups of rats by using c-Fos expression as a reflection of neural activity, combined with dual immunostaining for tyrosine hydroxylase (TH) or glutamic acid decarboxylase (GAD). Numbers of TH+/c-Fos+ neurons in the substantia nigra (SN) were not significantly different across groups, whereas those in the ventral tegmental area (VTA) were significantly different and greatest in PS recovery. Numbers of GAD+/c-Fos+ neurons in both VTA and SN were greatest in PS recovery. Thus, DA neuronal activity does not appear to be suppressed by local GABAergic neuronal activity during PS but might be altered in pattern by this inhibitory as well as other excitatory, particularly cholinergic, inputs such as to allow DA VTA neurons to become maximally active during PS and thereby contribute to the unique physiological and cognitive aspects of that state.
authors.affiliation: Department of Neurology and Neurosurgery, McGill University, Montreal Neurological Institute, 3801 University Street, Montreal, Quebec H3A 2B4, Canada.
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Maloney
authors.forename: Lynda
authors.initials: L
authors.lastname: Mainville
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Jones
mesh_terms: D000818:Animals; D002452:Cell Count; D004298:Dopamine / Q000378:metabolism*; D015870:Gene Expression / Q000502:physiology; D005968:Glutamate Decarboxylase / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D009433:Neural Inhibition / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D020127:Recovery of Function / Q000502:physiology; D012892:Sleep Deprivation / Q000378:metabolism* / Q000503:physiopathology; D012895:Sleep, REM / Q000502:physiology; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D017557:Ventral Tegmental Area / Q000166:cytology / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D005680:gamma-Aminobutyric Acid; D014446:Tyrosine 3-Monooxygenase; D005968:Glutamate Decarboxylase; D004298:Dopamine