title: Changes in 5-HT2A receptor expression in untreated, de novo patients with Parkinson's disease.
abstract: BACKGROUND
  Serotonin (5-HT) has long been implied in the pathophysiology of Parkinson's disease (PD). In addition, the 5-HT2A receptor is associated with the regulation of motor function and mood.
  
  
  OBJECTIVE
  To assess regional 5-HT2A receptor expression in unmedicated patients with de novo PD.
  
  
  METHODS
  Eight de novo, drug naïve patients with PD and eight healthy control subjects underwent a single photon emission computed tomography (SPECT) scan with the highly selective 5-HT2A radioligand 123I-5-I-R91150.
  
  
  RESULTS
  In de novo PD patients 5-HT2A receptor binding was significantly reduced in the anterior striatum and the premotor cortex in PD patients compared to controls. In addition, occipital binding was elevated in PD patients. No changes in 5-HT2A receptor binding were found in the prefrontal and parietal cortex.
  
  
  CONCLUSIONS
  In de novo PD patients, 5-HT2A receptor expression is changed in key areas of the basal ganglia-thalamocortical motor circuit and occipital cortex. This suggests altered 5-HT neurotransmission to contribute to development of PD motor and non-motor symptoms.
authors.affiliation: Department of Neuroscience, Maastricht University, Maastricht, The Netherlands Department of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Maartje
authors.initials: M
authors.lastname: Melse
authors.affiliation: Department of Neuroscience, Maastricht University, Maastricht, The Netherlands Department of Neurosurgery, University Hospital RWTH Aachen, Aachen, Germany.
authors.forename: Sonny K H
authors.initials: SK
authors.lastname: Tan
authors.affiliation: Department of Neuroscience, Maastricht University, Maastricht, The Netherlands Department of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Yasin
authors.initials: Y
authors.lastname: Temel
authors.affiliation: Department of Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Marinus J P G
authors.initials: MJ
authors.lastname: van Kroonenburgh
authors.affiliation: Department of Neuroscience, Maastricht University, Maastricht, The Netherlands Department of Psychiatry, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Albert F G
authors.initials: AF
authors.lastname: Leentjens
mesh_terms: D001479:Basal Ganglia / Q000000981:diagnostic imaging / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000000981:diagnostic imaging / Q000378:metabolism; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000378:metabolism*; D044402:Receptor, Serotonin, 5-HT2A / Q000378:metabolism*; D013788:Thalamus / Q000000981:diagnostic imaging / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D044402:Receptor, Serotonin, 5-HT2A
keywords: 5-HT$_{2A}$ receptor; Parkinson's disease; neuroimaging; serotonin