The Endocannabinoid System and Parkinson Disease

Dysregulation of the endocannabinoid system has been implicated in several neurodegenerative disorders including Parkinson disease (PD). Within the motor areas of the brain, cannabinoid and dopamine systems regulate motor function and synaptic plasticity by modulating excitatory and inhibitory neurotransmission. Alterations of this cross talk have been linked to the pathophysiology of PD and the maladaptive plasticity associated with the disabling motor complications caused by long-term use of L-DOPA. This chapter reviews the complex functional interactions between endocannabinoid and dopaminergic/glutamatergic systems in the basal ganglia, the contribution of endocannabinoid transmission dysfunction to PD and L-DOPA-induced dyskinesia, and recent preclinical studies using cannabinoid-based drugs for the pharmacotherapy of these pathologic conditions.