title: Brain acetylcholinesterase activity in mild cognitive impairment and early Alzheimer's disease.
abstract: OBJECTIVE
  Brain acetylcholinesterase activity was determined in healthy controls and in patients with mild cognitive impairment and early Alzheimer's disease.
  
  
  METHODS
  A specific acetylcholinesterase tracer, [methyl-(11)C]N-methyl-piperidyl-4-acetate ([(11)C]MP4A), and a three dimensional PET system with magnetic resonance coregistration were used for imaging.
  
  
  RESULTS
  There was a significant difference in the acetylcholinesterase activity in the hippocampus between the groups (p = 0.03), the mean (SD) acetylcholinesterase activity (k(3) values, min(-1)) being 0.114 (0.036) in controls, 0.098 (0.023) in mild cognitive impairment, and 0.085 (0.022) in Alzheimer's disease. The mini-mental state examination score showed no significant relation with acetylcholinesterase activity in any brain area in the combined mild cognitive impairment/Alzheimer group.
  
  
  CONCLUSIONS
  Hippocampal acetylcholinesterase activity is only slightly reduced in mild cognitive impairment and early Alzheimer's disease and so the value of in vivo acetylcholinesterase measurements in detecting the early Alzheimer process is limited.
authors.affiliation: Department of Neurology, University of Turku, FIN-20521 Turku, Finland. juta.rinne@pet.tyks.fi
authors.forename: J O
authors.initials: JO
authors.lastname: Rinne
authors.forename: V
authors.initials: V
authors.lastname: Kaasinen
authors.forename: T
authors.initials: T
authors.lastname: Järvenpää
authors.forename: K
authors.initials: K
authors.lastname: Någren
authors.forename: A
authors.initials: A
authors.lastname: Roivainen
authors.forename: M
authors.initials: M
authors.lastname: Yu
authors.forename: V
authors.initials: V
authors.lastname: Oikonen
authors.forename: T
authors.initials: T
authors.lastname: Kurki
mesh_terms: D000085:Acetates / Q000493:pharmacokinetics; D000110:Acetylcholinesterase / Q000378:metabolism*; D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000201:enzymology*; D000704:Analysis of Variance; D001921:Brain / Q000000981:diagnostic imaging / Q000201:enzymology*; D002250:Carbon Radioisotopes; D003072:Cognition Disorders / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000201:enzymology*; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000201:enzymology; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010880:Piperidines / Q000493:pharmacokinetics; D011237:Predictive Value of Tests; D012016:Reference Values; D014055:Tomography, Emission-Computed
chemical_list: D000085:Acetates; D002250:Carbon Radioisotopes; C100518:N-methyl-4-piperidyl acetate; D010880:Piperidines; D000110:Acetylcholinesterase