ADENOSINE RECEPTOR LIGANDS AND DIZOCILPINE-INDUCED ANTINOCICEPTION IN MICE

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.