Striatal dopaminergic neurons are lost with Parkinson's disease progression.

Increased numbers of dopaminergic neurons are described in the striatum of patients with Parkinson's disease. In postmortem striatal tissue from Parkinson's disease patients with short disease duration (< or =8 years), the number of dopaminergic neurons is approximately four times that in patients with long duration (> or =16 years). The data suggest the possibility that the presence of large numbers of these striatal dopaminergic neurons may be harmful and may accelerate the disease process. Alternatively, these neurons may be lost to the disease process.