Morphological and functional changes of striatal neurons with L‐dopa‐induced dyskinesia

Abstract

Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive loss of nigrostriatal dopaminergic neurons. 1 Patients with PD present with motor symptoms, such as resting tremor, akinesia, and rigidity. 2 Levo-dihydroxyphenylalanine (Ldopa) is the most effective drug for PD motor symptoms. 3 However, L-dopa treatment induces various motor complications, including abnormal involuntary movements, termed L-dopa-induced dyskinesia (LID). 4 After PD onset, 8.4% of Japanese patients develop dyskinesia within 5 years, 35.1% within 10 years, and 62.8% within 15 years, according to a 2006 local report. 5 Once developed, LID is incurable and treatment options are limited. 4 LID comprises peak-dose dyskinesia, diphasic dyskinesia, and off-period dystonia. Herein, we