Dopamine deficiency in parkinsonism

The etiology of progressive death of dopaminergic neurons in substantia nigra of Parkinson s disease brains remains unclear. Dopamine deficiency in Parkinson s disease is commonly treated with L-dopa and carbidopa, a periphera dopa decarboxylase inhibitor (Sinemet). Since its introduction, L-dopa has been shown to be effective in treating Parkinson s disease. However, high concentrations of L-dopa produce side effects such as psychosis, on-off effects, abnormal involuntary movements, and akinetic crisis. 

Scherman D, Desnos C, Darchen F, Poliak P, Javoy-Agid F, Agid Y. Striatal dopamine deficiency in Parkinson s disease role of aging. Ann Neurol 1989 26 551-557. 

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