title: Adenosine and caffeine modulate circadian rhythms in the Syrian hamster.
abstract: Extracellular adenosine accumulates in some brain areas during sleep deprivation. In Syrian hamsters, both sleep deprivation and adenosine A1 agonists can inhibit phase shifts of circadian rhythms to light at night. Sleep deprivation in the day (sleep period) can shift circadian phase. We examined whether the A1 agonist N-CHA mimics this effect. N-CHA (i.p. or i.c.) in the mid-sleep period induced dose-dependent shifts similar to those induced by 3 h sleep deprivation. The adenosine antagonist caffeine administered systemically at the mid-sleep period induced arousal without shifts, and dose-dependently attenuated shifts to a 3 h sleep deprivation procedure (running in a novel wheel). Adenosine may participate in resetting of the circadian clock by manipulations of behavioral state.
authors.affiliation: Department of Psychology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: M C
authors.initials: MC
authors.lastname: Antle
authors.forename: N M
authors.initials: NM
authors.lastname: Steen
authors.forename: R E
authors.initials: RE
authors.lastname: Mistlberger
mesh_terms: D000241:Adenosine / Q000819:agonists* / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D002940:Circadian Rhythm / Q000187:drug effects* / Q000502:physiology; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D007150:Immunohistochemistry; D008297:Male; D008647:Mesocricetus; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000187:drug effects / Q000378:metabolism; D058906:Purinergic P1 Receptor Agonists; D058915:Purinergic P1 Receptor Antagonists; D018047:Receptors, Purinergic P1 / Q000378:metabolism; D012890:Sleep / Q000187:drug effects* / Q000502:physiology; D012892:Sleep Deprivation / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D013493:Suprachiasmatic Nucleus / Q000187:drug effects* / Q000378:metabolism
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D058906:Purinergic P1 Receptor Agonists; D058915:Purinergic P1 Receptor Antagonists; D018047:Receptors, Purinergic P1; C027513:N(6)-cyclohexyladenosine; D002110:Caffeine; D000241:Adenosine