Dopa decarboxylase activity of the living human brain.
AUTOR(ES)
Gjedde, A
RESUMO
Monoaminergic neurons use dopa decarboxylase (DDC; aromatic-L-amino-acid carboxy-lyase, EC 4.1.1.28) to form dopamine from L-3,4-dihydroxyphenylalanine (L-dopa). We measured regional dopa decarboxylase activity in brains of six healthy volunteers with 6-[18F]fluoro-L-dopa and positron emission tomography. We calculated the enzyme activity, relative to its Km, with a kinetic model that yielded the relative rate of conversion of 6-[18F]fluoro-L-dopa to [18F]fluorodopamine. Regional values of relative dopa decarboxylase activity ranged from nil in occipital cortex to 1.9 h-1 in caudate nucleus and putamen, in agreement with values obtained in vitro.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=51310Documentos Relacionados
- Elevated dopa decarboxylase activity in living brain of patients with psychosis.
- Magnetic localization of neuronal activity in the human brain.
- Benzodiazepine receptors mediate regional blood flow changes in the living human brain.
- Acute hypoxia increases ornithine decarboxylase activity and polyamine concentrations in fetal rat brain.
- On the Identity of DOPA Decarboxylase and 5-Hydroxytryptophan Decarboxylase