Expression of dyskinetic movements and turning behaviour in subchronic l-DOPA 6-hydroxydopamine-treated rats is influenced by the testing environment

Sensitisation in contralateral turning behaviour and induction of abnormal involuntary movements (AIMs) after subchronic intermittent l-DOPA were compared for their predictive validity as model of parkinsonian dyskinetic movements. l-DOPA treatment produced sensitisation in turning behaviour in 6-hydroxydopamine-lesioned rats, when animals were evaluated in hemispherical bowls but not in cages. In contrast, sensitisation in AIMs was obtained both in hemispherical bowls and cages. Results provide evidence that the choice of the environment used in evaluation of AIMs and turning behaviour is of crucial importance.