Chronic subthalamic nucleus stimulation and striatal D2 dopamine receptors in Parkinson's disease--A [(11)C]-raclopride PET study.

Dept. of Neurology D (Pr. G. Chazot) and INSERM U 534, Hôpital Neurologique Pierre Wertheimer, 59 Bd Pinel, 69003 Lyon, France.
Journal of Neurology (Impact Factor: 3.84). 11/2003; 250(10):1219-23. DOI: 10.1007/s00415-003-0188-z
Source: PubMed

ABSTRACT Subthalamic nucleus (STN) stimulation mechanism of action remains a matter for debate. In animals, an increased striatal dopamine (DA) release due to STN stimulation has been reported.
To determine in Parkinson's disease (PD) patients using positron emission tomography (PET) and [11C]-Raclopride, whether STN stimulation induces a striatal DA release.
Nine PD patients with bilateral STN stimulation were enrolled and underwent two [11C]-Raclopride PET scans. The scans were randomly performed in off and on stimulation conditions. Striatal [11C]-Raclopride binding potential (BP) was calculated using regions of interest and statistical parametric mapping.
For PD patients, the mean [(11C]-Raclopride BP (+/- SD) were, in Off stimulation condition: 1.7 +/- 0.3 for the right caudate nucleus, 1.8 +/- 0.4 for the left caudate nucleus, 2.6 +/- 0.5 for the right putamenand 2.6 +/- 0.5 for the left putamen. In On stimulation condition: 1.7 +/- 0.4 for the right caudate nucleus, 1.9 +/- 0.5 for the left caudate nucleus, 2.8 +/- 0.7 for the right putamen and 2.7 +/- 0.8 for the left putamen. No significant difference of BP related to the stimulation was noted.
STN stimulation does not produce significant variations of striatal DA release as assessed by PET and [11C]-Raclopride.

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