Dyskinesia and wearing‐off following dopamine D1 agonist treatment in drug‐naive 1‐Methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine‐lesioned primates

Abstract
The motor effects of the short‐acting, full D1 agonist SKF 82958 were studied in three drug‐naive, 1‐methyl‐4‐phenyl‐1, 2, 3, 6‐tetrahydropyridine‐lesioned, parkinsonian monkeys treated for 4 weeks. D1 receptor stimulation with SKF 82958 effectively relieved parkinsonism but induced choreic dyskinesia (n = 2) and a shorter duration of motor benefit (n = 3) over time. Isolated, short‐lived D1 receptor activation would not appear to confer advantage over levodopa for dyskinesia prevention. Our data also support the involvement of postsynaptic dopamine receptor mechanisms in the wearing‐off phenomenon seen in levodopa‐treated parkinsonian patients.