title: Adenosine A2A, but not A1, receptors mediate the arousal effect of caffeine.
abstract: Caffeine, a component of tea, coffee and cola, induces wakefulness. It binds to adenosine A1 and A2A receptors as an antagonist, but the receptor subtype mediating caffeine-induced wakefulness remains unclear. Here we report that caffeine at 5, 10 and 15 mg kg(-1) increased wakefulness in both wild-type mice and A1 receptor knockout mice, but not in A2A receptor knockout mice. Thus, caffeine-induced wakefulness depends on adenosine A2A receptors.
authors.affiliation: Department of Molecular Behavioral Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan.
authors.forename: Zhi-Li
authors.initials: ZL
authors.lastname: Huang
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Qu
authors.forename: Naomi
authors.initials: N
authors.lastname: Eguchi
authors.forename: Jiang-Fan
authors.initials: JF
authors.lastname: Chen
authors.forename: Michael A
authors.initials: MA
authors.lastname: Schwarzschild
authors.forename: Bertil B
authors.initials: BB
authors.lastname: Fredholm
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Urade
authors.forename: Osamu
authors.initials: O
authors.lastname: Hayaishi
mesh_terms: D000818:Animals; D001143:Arousal / Q000187:drug effects* / Q000502:physiology*; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D051379:Mice; D018345:Mice, Knockout; D043705:Receptor, Adenosine A2A / Q000502:physiology*; D014851:Wakefulness / Q000187:drug effects / Q000502:physiology
chemical_list: D000697:Central Nervous System Stimulants; D043705:Receptor, Adenosine A2A; D002110:Caffeine