title: The 1976C>T polymorphism in the adenosine A2A receptor gene does not affect the vasodilator response to adenosine in humans in vivo.
abstract: The 1976C>T polymorphism in the adenosine A2A receptor gene (ADORA2A) modulates the psychological response to administration of the adenosine receptor antagonist caffeine. We quantified the vascular response to adenosine and caffeine to determine the relevance of this variant allele in the physiological response to these agents. We selected 10 study participants with the TT genotype and 10 CC controls, matched for activities of other proteins involved in the metabolism of adenosine. The vasodilator response to the intrabrachial administration of adenosine (0.5, 1.5, 5.0, 15.0, and 50.0 microg/min/dl; venous occlusion plethysmography) was not different between the groups (P=0.4). In addition, the effect of subsequent administration of caffeine (90 microg/min/dl) was not different (P=0.7). We conclude that the 1976C>T polymorphism does not affect the vascular response to adenosine and caffeine in humans in vivo. Therefore, this polymorphism does not contribute to the variation in the effects of adenosine receptor stimulation.
authors.affiliation: Department of Pharmacology, Radboud University Nijmegen Medical Center, The Netherlands. N.Riksen@aig.umcn.nl
authors.forename: Niels P
authors.initials: NP
authors.lastname: Riksen
authors.forename: Barbara
authors.initials: B
authors.lastname: Franke
authors.forename: Petra
authors.initials: P
authors.lastname: van den Broek
authors.forename: Paul
authors.initials: P
authors.lastname: Smits
authors.forename: Gerard A
authors.initials: GA
authors.lastname: Rongen
mesh_terms: D000659:AMP Deaminase / Q000235:genetics; D000241:Adenosine / Q000494:pharmacology; D000328:Adult; D000483:Alleles; D001483:Base Sequence; D002110:Caffeine / Q000494:pharmacology; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D010597:Pharmacogenetics; D020641:Polymorphism, Single Nucleotide; D043705:Receptor, Adenosine A2A / Q000235:genetics* / Q000502:physiology*; D014664:Vasodilation / Q000187:drug effects / Q000235:genetics* / Q000502:physiology
chemical_list: D017931:DNA Primers; D043705:Receptor, Adenosine A2A; D002110:Caffeine; D000659:AMP Deaminase; C514117:AMPD1 protein, human; D000241:Adenosine