D3 dopamine receptor-preferring [11C]PHNO PET imaging in Parkinson patients with dyskinesia. (19th January 2016)

• Record Type: Journal Article
• Authors: Payer, Doris E.; Guttman, Mark; Kish, Stephen J.; Tong, Junchao; Adams, John R.; Rusjan, Pablo; Houle, Sylvain; Furukawa, Yoshiaki; Wilson, Alan A.; Boileau, Isabelle
• Is Part Of: Neurology. Volume 86:Number 3(2016)
• Publication Date: 2016-01-19
• Subjects: Neurology -- Periodicals; Neurology -- Periodicals; Neurologie -- Périodiques; 616.8
• DOI: 10.1212/WNL.0000000000002285
• Languages: English
• ISSNs: 0028-3878

Abstract

Abstract : Objective: To investigate whether levodopa-induced dyskinesias (LID) are associated with D3 overexpression in levodopa-treated humans with Parkinson disease (PD). Methods: In this case-control study, we used PET with the D3 -preferring radioligand [ 11 C]-(+)-PHNO to estimate D2/3 receptor binding in patients with levodopa-treated PD with LID (n = 12) and without LID (n = 12), and healthy control subjects matched for age, sex, education, and mental status (n = 18). Results: Compared to nondyskinetic patients, those with LID showed heightened [ 11 C]-(+)-PHNO binding in the D3 -rich globus pallidus. Both PD groups also showed higher binding than controls in the sensorimotor division of the striatum. In contrast, D2/3 binding in the ventral striatum was lower in patients with LID than without, possibly reflecting higher dopamine levels. Conclusions: Dopaminergic abnormalities contributing to LID may include elevated D2/3 binding in globus pallidus, perhaps reflecting D3 receptor upregulation. The findings support therapeutic strategies that target and diminish activity at D3 to prevent LID.