L-Dopa Uptake and Decarboxylation in the Brain
L-dihydroxyphenylalanine (L-DOPA) therapy has been well accepted in order to improve extrapyramidal motor disturbance in Parkinson disease, and the uptake and metabolism of loaded DOPA as a precursor of dopamine (DA) in the brain has been studied, using autoradiography and high-resolution positron emission tomography (PET). However, no detailed anatomical information has been provided. It is known that L-DOPA is transformed by a second step catecholamine-synthesizing enzyme, aromatic L-amino acid decarboxylase (AADC). In the present study, we examined the localization of this enzyme, and elucidated in what neuronal structures L-DOPA is converted to DA, using immunohistochemistry in conjunction with the antisera, anti-DA as well as anti-AADC.
KeywordsDorsal Raphe Nucleus Sodium Metabisulfite Nickel Ammonium Positron Emission Tomographic Study Detailed Anatomical Information
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