CGS 21680 exerts marked antidystonic effects in a genetic model of paroxysmal dyskinesia.

The effect of the adenosine A(2A) receptor agonist CGS 21680 (2-carboxyethyl)phenylethylamino]-5'-N-ethylcarbonyamido-ade nosine) on severity of dystonia was examined in genetically dystonic hamsters which exhibit attacks of dystonic and choreoathetotic disturbances in response to mild stress. CGS 21680 significantly reduced the severity of dystonia (0.5, 1.0 and 2.0 mg/kg i.p.). The marked antidystonic effects of CGS 21680 in the hamster model suggest that this compound may represent an interesting candidate for the therapy of paroxysmal dystonia. Furthermore, the present data indicate that the precipitating effect of caffeine in patients with paroxysmal dystonia is probably due to its adenosine receptor antagonistic action.