Mitochondrial energy crisis as a mechanism for nigral cell death

Studies on mitochondrial respiratory enzymes in Parkinson’s disease are reviewed. The presence of abnormalities in Complex I of the mitochondrial respiratory chain was described in Parkinson’s disease by several groups of investigators utilizing different methods. These abnormalities do not seem to be a primary defect of Parkinson’s disease. Instead, they seem to be a consequence of long-standing noxious stimuli to substantia nigra. Dopaminergic neurons in substantia nigra appear to have a unique property with reduced tolerance to various noxious stimuli. Further studies on mitochondria seem to be important for the elucidation of Parkinson’s disease.