MPTP Neurotoxicity And The “Biochemical” Blood-Brain Barrier
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About 25 years ago, major breakthroughs were made in our understanding of the neurochemistry of the basal ganglia and the biochemical pathology of Parkinson’s disease, which eventually led to the successful introduction of levodopa as replacement therapy for this malady. This dramatic success story, especially after the subsequent introduction of peripheral DOPA decarboxylase inhibitors and dopamine receptor agonists as adjuvants, was hailed as one of the best examples of how basic biomedical research can lead to rational therapies for human diseases. Meanwhile, the cause of Parkinson’s disease, i.e. the progressive degeneration of nigrostriatal dopaminergic neurons, remained unknown. Furthermore, replacement therapy, which was once considered revolutionary, was found to be of little help in the treatment of subjects with advanced Parkinsonism and entirely ineffective in arresting the inexorable progression of Parkinson’s disease. Another important fact that emerged in the last decade concerns the lack of evidence that Parkinson’s disease is a genetic disorder, as evidenced by the absence of increased concordance among identical twins. This led to the belief that it may be caused by environmental factors (if it is not nature, it must be nurture).
KeywordsMonoamine Oxidase Clorgy Line Brain Microvessels Monoamine Oxidase Activity Nigrostriatal Dopaminergic Neuron
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