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Decreased intestinal acetylcholinesterase in early Parkinson disease: An 11C-donepezil PET study
Tatyana D Fedorova1, Louise B Seidelin2, Karoline Knudsen2
1From the Department of Nuclear Medicine and PET-Centre (T.D.F., L.B.S., K.K., A.C.S., N.P., D.J.B., P.B.) and Department of Neurology (J.G.), Aarhus University Hospital, Denmark. tdf@clin.au.dk.
Objective:
To investigate systemic levels of acetylcholinesterase in early Parkinson disease (PD) with 11C-donepezil PET, a potential marker of parasympathetic innervation.
Methods:
This was a cross-sectional study with 19 patients with early-stage PD (disease duration 1.5 ± 0.6 years) and 16 age-matched controls who had clinical assessments, olfaction tests, and 11C-donepezil PET to measure acetylcholinesterase density in peripheral organs.
Results:
The patients with PD showed significantly reduced 11C-donepezil uptake in the small intestine (-14%, p = 0.018), colon (-22%, p < 0.001), and kidneys (-14%, p = 0.028). No difference in myocardial or pancreatic acetylcholinesterase levels was seen.
Conclusion:
We found significantly decreased 11C-donepezil signal in the intestine and kidneys of patients with early PD, suggesting that parasympathetic denervation is present early in the disease course.
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