[Mechanisms and treatments of Parkinson disease].

The loss of dopaminergic melanized neurons of the substantia nigra is the main lesion of Parkinson's disease. This cell death, of unknown origin, is accompanied by the formation of free radicals and the occurrence of oxidative stress. The nigro-striatal dopaminergic hypoactivity induces a disinhibition of the subthalamo-pallidal structures responsible for a frontal cortex hypoactivity, at the origin of akinesia. Levodopa is the most effective treatment of Parkinson's disease, but exposes to motor complications that new therapeutic strategies try to limit. The neurosurgical treatment, especially deep brain stimulation, is applied to few selected patients.