title: Blockage of dopaminergic D(2) receptors produces decrease of REM but not of slow wave sleep in rats after REM sleep deprivation.
abstract: Dopamine (DA) has, as of late, become singled out from the profusion of other neurotransmitters as what could be called a key substance, in the regulation of the sleep-wake states. We have hypothesized that dopaminergic D(2) receptor blockage induced by haloperidol could generate a reduction or even an ablation of rapid eye movement (REM) sleep. Otherwise, the use of the selective D(2) agonist, piribedil, could potentiate REM sleep. Electrophysiological findings demonstrate that D(2) blockage produced a dramatic reduction of REM sleep during the rebound (REB) period after 96 h of REM sleep deprivation (RSD). This reduction of REM sleep was accompanied by an increment in SWS, which is possibly accounted for the observed increase in the sleep efficiency. Conversely, our findings also demonstrate that the administration of piribedil did not generate additional increase of REM sleep. Additionally, D(2) receptors were found down-regulated, in the haloperidol group, after RSD, and subsequently up-regulated after REB group, contrasting to the D(1) down-regulation at the same period. In this sense, the current data indicate a participation of the D(2) receptor for REM sleep regulation and consequently in the REM sleep/SWS balance. Herein, we propose that the mechanism underlying the striatal D(2) up-regulation is due to an effect as consequence of RSD which originally produces selective D(2) supersensitivity, and after its period probably generates a surge in D(2) expression. In conclusion we report a particular action of the dopaminergic neurotransmission in REM sleep relying on D(2) activation.
authors.affiliation: Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil. mmeirasantoslima@psicobio.epm.br
authors.forename: Marcelo M S
authors.initials: MM
authors.lastname: Lima
authors.forename: Monica L
authors.initials: ML
authors.lastname: Andersen
authors.forename: Angela B
authors.initials: AB
authors.lastname: Reksidler
authors.forename: Andressa
authors.initials: A
authors.lastname: Silva
authors.forename: Adriano
authors.initials: A
authors.lastname: Zager
authors.forename: Sílvio M
authors.initials: SM
authors.lastname: Zanata
authors.forename: Maria A B F
authors.initials: MA
authors.lastname: Vital
authors.forename: Sergio
authors.initials: S
authors.lastname: Tufik
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D010891:Piribedil / Q000494:pharmacology; D051381:Rats; D017447:Receptors, Dopamine D1 / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D012890:Sleep / Q000187:drug effects / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology*; D012895:Sleep, REM / Q000187:drug effects / Q000502:physiology*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D014851:Wakefulness / Q000187:drug effects / Q000502:physiology
chemical_list: D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D010891:Piribedil; D014446:Tyrosine 3-Monooxygenase; D006220:Haloperidol