Evidence for impaired presynaptic dopamine function in parkinsonian patients with motor fluctuations

Détails

ID Serval
serval:BIB_52546207B30B
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Evidence for impaired presynaptic dopamine function in parkinsonian patients with motor fluctuations
Périodique
Journal of Neural Transmission
Auteur(s)
de la Fuente-Fernandez  R., Pal  P. K., Vingerhoets  F. J., Kishore  A., Schulzer  M., Mak  E. K., Ruth  T. J., Snow  B. J., Calne  D. B., Stoessl  A. J.
ISSN
0300-9564 (Print)
Statut éditorial
Publié
Date de publication
2000
Volume
107
Numéro
1
Pages
49-57
Notes
Journal Article
Research Support, Non-U.S. Gov't
Résumé
We used [18F]6-fluorodopa (FD) positron emission tomography (PET) to examine the severity of nigrostriatal dopaminergic dysfunction in 67 patients with Idiopathic Parkinsonism (IP), 52 with fluctuations and 15 with a stable response to levodopa. FD uptake (Ki) was reduced by 12% in the caudate (p = 0.08) and by 28% in the putamen (p = 0.0004) of patients with fluctuations compared to those with a stable response. However, there was considerable overlap of FD Ki values between the two groups. The fluctuators had a longer symptom duration (11.6 +/- 5.7 years) than the patients with a stable response to levodopa (4.3 +/- 2.4 years; p < 0.0001) and the age of onset of symptoms was earlier in the fluctuators (43.9 +/- 8.9 versus 54.1 +/- 10.4; p = 0.0004). Similar reductions in FD Ki in the fluctuators persisted following adjustment for these variables (7.5% in the caudate and 26% in the putamen; p = n.s. and 0.007, respectively). When smaller groups (n = 15 each) were matched for duration of symptoms, the reduction in caudate Ki in the fluctuators was only 1.9% (p = n.s.), but there was still a 24% reduction in putamen Ki (p = 0.05). These findings suggest that fluctuators and non-fluctuators may differ in the severity of their nigrostriatal damage and provide modest support for the hypothesis that fluctuations may in part reflect altered "buffering" capacity of dopaminergic nerve terminals. However, the considerable overlap between groups suggests that other factors such as altered postsynaptic mechanisms and/or increased turnover of dopamine may make a substantial contribution to the development of motor fluctuations.
Mots-clé
Antiparkinson Agents/administration & dosage Dihydroxyphenylalanine/analogs & derivatives/diagnostic use/pharmacokinetics Dopamine/*metabolism Female Fluorine Radioisotopes/diagnostic use/pharmacokinetics Humans Levodopa/administration & dosage Male Middle Aged Motor Neurons/*metabolism Movement Disorders/drug therapy/*metabolism/radionuclide imaging Parkinson Disease/drug therapy/*metabolism/radionuclide imaging Presynaptic Terminals/*metabolism Substantia Nigra/cytology/metabolism Tomography, Emission-Computed
Pubmed
Web of science
Création de la notice
25/01/2008 13:49
Dernière modification de la notice
03/03/2018 17:13
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