title: Expression pattern of FOS in orexin neurons during sleep induced by an adenosine A2A receptor agonist.
abstract: The present study examined the expression pattern of FOS in the hypothalamic peptide neurons during the sleep-dominant state induced by an adenosine A2A receptor agonist. The control rats, those that received the microdialysis-perfusion of their ventral striatum with artificial cerebrospinal fluid in the dark-active phase, spent 24% of the 90-min period prior to sacrifice in non-rapid eye movement (non-REM) sleep and 2.3% of that in REM sleep. These rats exhibited FOS, a transcription factor, in 21% of their orexin neurons and in 1.0% of their melanin-concentrating hormone (MCH) neurons in the perifornical/lateral hypothalamic areas. However, the rats perfused with 50 microM CGS21680, an adenosine A2A receptor agonist, spent 60% of the 90-min period prior to sacrifice in non-REM sleep and 11% of that in REM sleep. These rats exhibited FOS in 1.7% of their orexin neurons and FOS in 0.5% of their MCH neurons. When the sleep-dominant state was disturbed by mild stimulation and the rats were kept in the sleepy state by treatment with a sleep-inducing dose of CGS21680, the rats exhibited FOS in 13.3% of their orexin neurons, which percentage was about half of that for the control rats. These results suggest that the sleep-promoting process induced by this adenosine A2A receptor agonist was associated with a decline in the activity of orexin neurons. MCH neurons are not likely to change their activities during this sleep-promoting process.
authors.affiliation: Department of Neuropsychiatry, Osaka Medical College, Takatsuki, Osaka 569-8686, Japan. knssat@yahoo.co.jp
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Satoh
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Matsumura
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanbayashi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Takahito
authors.initials: T
authors.lastname: Urakami
authors.forename: Tomoko
authors.initials: T
authors.lastname: Nakajima
authors.forename: Nobuko
authors.initials: N
authors.lastname: Kimura
authors.forename: Seiji
authors.initials: S
authors.lastname: Nishino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoneda
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D058908:Adenosine A2 Receptor Agonists; D000818:Animals; D002452:Cell Count / Q000379:methods; D015870:Gene Expression / Q000187:drug effects; D007028:Hypothalamic Hormones / Q000378:metabolism; D007031:Hypothalamus / Q000166:cytology; D007150:Immunohistochemistry / Q000379:methods; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D008543:Melanins / Q000378:metabolism; D009474:Neurons / Q000187:drug effects*; D009479:Neuropeptides / Q000378:metabolism*; D016761:Oncogene Proteins v-fos / Q000378:metabolism*; D064446:Orexin Receptors; D000068797:Orexins; D010627:Phenethylamines / Q000494:pharmacology*; D010907:Pituitary Hormones / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D012890:Sleep / Q000187:drug effects*; D018709:Statistics, Nonparametric
chemical_list: D058908:Adenosine A2 Receptor Agonists; D007028:Hypothalamic Hormones; D047908:Intracellular Signaling Peptides and Proteins; D008543:Melanins; D009479:Neuropeptides; D016761:Oncogene Proteins v-fos; D064446:Orexin Receptors; D000068797:Orexins; D010627:Phenethylamines; D010907:Pituitary Hormones; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; C061282:2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine; C019463:melanin-concentrating hormone; D000241:Adenosine