Estimation of regional cerebral utilization of [11C]-L-3,4-dihydroxy-phenylalanine (DOPA) in the primate by positron emission tomography.
The intracerebral kinetics of [11C]-labelled L-3,4-dihydroxyphenylalanine, L-DOPA, was investigated in rhesus monkeys by positron emission tomography (PET). Through the labelling of the L-DOPA molecule in different positions and observation of a series of pharmacological challenges it was possible to establish that the kinetic conversion of the radiotracer in the striatum represents the process of decarboxylation to [11C]-labelled dopamine. The rate constant for this process can be estimated using a two-compartment model. The use of [11C]-L-DOPA and PET will thus provide a possibility for in vivo studies of blood-brain barrier transport of the amino acid as well as for the estimation of the ability for brain tissue to decarboxylate the tracer by the action of aromatic L-amino acid decarboxylase.
Tedroff
J
J
Department of Neurology, University Hospital, Uppsala, Sweden.
Aquilonius
S M
SM
Hartvig
P
P
Lundqvist
H
H
Bjurling
P
P
Långström
B
B
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging*; D003342:Corpus Striatum / Q000000981:diagnostic imaging; D004298:Dopamine / Q000378:metabolism; D005260:Female; D007980:Levodopa / Q000493:pharmacokinetics*; D008253:Macaca mulatta; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000000981:diagnostic imaging; D011854:Radiochemistry; D013329:Structure-Activity Relationship; D014055:Tomography, Emission-Computed
D007980:Levodopa; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D004298:Dopamine