title: Quantification of nicotinic acetylcholine receptors in Parkinson's disease with (123)I-5IA SPECT.
abstract: We quantified in vivo brain nicotinic acetylcholine receptor (nAChR) distributions in patients with Parkinson's disease (PD) and evaluated correlations between nAChR distributions and clinical variables of the patients, especially dopaminergic medications. Ten patients with PD without dementia underwent 5-(123)I-iodo-3-(2(S)-azetidinylmethoxy)pyridine ((123)I-5IA) single photon emission computed tomography (SPECT) and the data were compared with those of 10 age-matched healthy volunteers. Correlation analyses between (123)I-5IA distribution volumes (DVs) in each brain region and clinical variables of the patients were also performed. The PD group showed a statistically significant decrease (20-25%) in the brainstem and frontal cortex as compared with the control group. Although age, duration of disease, daily dose of levodopa, duration of PD medication use, and scores on the motor section of Unified Parkinson's Disease Rating Scale were not significantly correlated with DV values in any brain regions, high daily doses of dopamine agonist showed a significant negative correlation with DVs in the cerebellum, and temporal, parietal and occipital cortices. These findings suggest that patients with PD without dementia can show reductions especially in the brainstem and frontal cortex. They also suggest that dopamine agonists can have a negative influence on the distribution of nAChRs.
authors: Human Brain Research Center, Kyoto University Graduate School of Medicine, Shogoin, Kyoto, Japan.
authors: Naoya
authors: N
authors: Oishi
authors: Kazuo
authors: K
authors: Hashikawa
authors: Hidefumi
authors: H
authors: Yoshida
authors: Koichi
authors: K
authors: Ishizu
authors: Masashi
authors: M
authors: Ueda
authors: Hidekazu
authors: H
authors: Kawashima
authors: Hideo
authors: H
authors: Saji
authors: Hidenao
authors: H
authors: Fukuyama
mesh_terms: D000368:Aged; D001384:Azetidines / Q000493:pharmacokinetics*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism; D011725:Pyridines / Q000493:pharmacokinetics*; D011978:Receptors, Nicotinic / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: C426745:5-iodo-3-(2-azetidinylmethoxy)pyridine; D001384:Azetidines; D011725:Pyridines; D011978:Receptors, Nicotinic