Abstract
Interactions between adenosine receptor ligands and dizocilpine (uncompetitive NMDA receptor antagonist) was studied in antinociceptive, writhing test in mice. Minimal effective, antinociceptive doses of adenosine receptor agonists were: 0.1 mg/kg (CPAAl receptor agonist), 0.05 mg/kg (CUS 21680A2 receptor agonist), and 0.005 mg/kg (NECAA1/A2 agonist). Generally, these agonists did not potentiate the subthreshold dose of dizocilpine (0.05 mg/kg). Of all adenosine receptor antagonists used, only caffeine (A1 and A2 antagonist) reversed dizocilpine-induced (0.1 mg/kg) antinociception dose-dependently. These findings indicate that dizocilpine-induced antinociception in the writhing test is only partly influenced by adenosine receptor ligands.