Mechanism of 6-hydroxydopamine neurotoxicity
The catecholaminergic neurotoxin 6-hydroxydopamine (6-OHDA) has recently been found to be formed endogenously in patients suffering from Parkinson’s disease. In this article, we highlight the latest findings on the biochemical mechanism of 6-OHDA toxicity. 6-OHDA has two ways of action: it easly forms free radicals and it is a potent inhibitor of the mitochondrial respiratory chain complexes I and IV. The inhibition of respiratory enzymes by 6-OHDA is reversible and insensitive towards radical scavengers and iron chelators with the exception of desferrioxamine. We conclude that free radicals ate not involved in the interaction between 6-OHDA and the respiratory chain and that the two mechanisms are biochemically independent, although they may act synergistically in vivo.
KeywordsDopaminergic Neuron Mitochondrial Respiration Iron Chelator Dopamine Neuron Mitochondrial Respiratory Chain Complex
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