title: Effects of A(1) and A(2A) adenosine receptor ligands in mouse acute models of pain.
abstract: The effects of selective A(1) and A(2A) adenosine receptor compounds in two mouse models of acute nociception were studied: acetic acid-induced writhing and the hot plate assays. Stimulation of A(1) receptors by 2-chloro-N(6)-cyclopentyl-adenosine (CCPA, 0.01-0.1 mg/kg, i.p.; A(1)K(i)=6 nM) or blockade of A(2A) receptors by 5-amino-7-(beta-phenylethyl)-2-(8-furyl)pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine (SCH58261, 1-10 mg/kg, i.p.; A(2)(A)K(i)=1.3 nM) produced anti-nociceptive effects. At the highest dose tested, CCPA and SCH58261 reduced the number of writhings by 79 and 99%, respectively. On the contrary, the A(1) antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) (A(1)K(i)=2.8 nM) and the A(2A) agonist 2-(4-[2-carboxyethyl])phenethylamino-5'-N-ethylcarboxamido-adenosine-hydrochloride (GGS21680) produced pro-nociceptive effects in both tests. These findings suggest for the first time that blockade of A(2A) adenosine receptors produces anti-nociceptive effects.
authors.affiliation: Schering-Plough Research Institute, San Raffaele Science Park, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Bastia
authors.forename: Katia
authors.initials: K
authors.lastname: Varani
authors.forename: Angela
authors.initials: A
authors.lastname: Monopoli
authors.forename: Rosalia
authors.initials: R
authors.lastname: Bertorelli
mesh_terms: D000208:Acute Disease; D000241:Adenosine / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D008024:Ligands; D051379:Mice; D009619:Nociceptors / Q000187:drug effects; D010146:Pain / Q000378:metabolism* / Q000523:psychology; D010147:Pain Measurement / Q000379:methods; D011743:Pyrimidines / Q000494:pharmacology; D043705:Receptor, Adenosine A2A; D018047:Receptors, Purinergic P1 / Q000378:metabolism*; D014230:Triazoles / Q000494:pharmacology
chemical_list: C098657:5-amino-7-(2-phenylethyl)-2-(2-furyl)pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c)pyrimidine; D008024:Ligands; D011743:Pyrimidines; D043705:Receptor, Adenosine A2A; D018047:Receptors, Purinergic P1; D014230:Triazoles; C058394:2-chloro-N(6)cyclopentyladenosine; D000241:Adenosine