ACUTE TREATMENT OF MICE WITH HIGH-DOSES OF CAFFEINE - AN ANIMAL-MODEL FOR CHOREIFORM MOVEMENT

Injection of caffeine at a dose of 35 to 70 mg/kg causes choreiform (dance-like) movements in NIH Swiss mice in a dose-dependent manner. The effect is less pronounced in mice that had chronically ingested caffeine for 7 days. The A(2a) selective adenosine agonist 2-[(2-amino-ethylamino)carbonylethylphenylethylamino]-5'-N-ethylcarboxamidoadenosine (APEC), but not the A(1) selective agonist N-6-cyclohexyladenosine (CHA), diminished caffeine-elicited choreiform movement. The data suggest involvement of A(2a)-adenosine receptors in the appearance of choreiform movements. The dopamine antagonist haloperidol also reduced the chorea movements elicited by caffeine, but high doses were required. The calcium-channel blocker nitrendipine reduced the choreiform movements. These animals could provide a model for further investigation of the mechanisms underlying choreiform movements; as well as possible therapeutic approaches to certain choreas in humans related either to disease states (e.g., Huntington's disease or Tourette's syndrome) or to side effects of drug treatments. (C) 1993 Wiley-Liss, Inc.