title: Orexin neurons of the hypothalamus express adenosine A1 receptors.
abstract: Adenosine is a putative sleep factor with effects mainly mediated by the A1 receptor. Recent studies have implicated the hypothalamic orexin/hypocretin-containing neurons in the control of sleep-wakefulness. To help determine if adenosine might play a role in the control of orexin neurons, immunohistochemistry was used to characterize the distribution of adenosine A1 receptor protein on the orexinergic neurons. About 30% of orexin-containing neurons were labeled. The data supports the presence of adenosine A1 receptors on orexinergic neurons and suggests a possible substrate for a functional role of adenosine in the regulation of orexinergic activity.
authors.affiliation: Department of Psychiatry, Harvard Medical School, VA Boston Healthcare System, Brockton VA Medical Center, Brockton, MA, USA. mthakkar@hms.harvard.edu
authors.forename: Mahesh M
authors.initials: MM
authors.lastname: Thakkar
authors.forename: Stuart
authors.initials: S
authors.lastname: Winston
authors.forename: Robert W
authors.initials: RW
authors.lastname: McCarley
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000241:Adenosine / Q000378:metabolism*; D000818:Animals; D020532:Basal Nucleus of Meynert / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D002452:Cell Count; D005455:Fluorescent Antibody Technique; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D009433:Neural Inhibition / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D064446:Orexin Receptors; D000068797:Orexins; D017729:Presynaptic Terminals / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D018047:Receptors, Purinergic P1 / Q000378:metabolism*; D012890:Sleep / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*
chemical_list: D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D064446:Orexin Receptors; D000068797:Orexins; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D018047:Receptors, Purinergic P1; D000241:Adenosine; D000109:Acetylcholine