title: In vivo measurement of plaque burden in a mouse model of Alzheimer's disease.
abstract: OBJECTIVE
  To demonstrate an MRI method for directly visualizing amyloid-beta (Abeta) plaques in the APP/PS1 transgenic (tg) mouse brain in vivo, and show that T1rho relaxation rate increases progressively with Alzheimer's disease (AD)-related pathology in the tg mouse brain.
  
  
  METHODS
  We obtained in vivo MR images of a mouse model of AD (APP/PS1) that overexpresses human amyloid precursor protein, and measured T1rho via quantitative relaxometric maps.
  
  
  RESULTS
  A significant decrease in T1rho was observed in the cortex and hippocampus of 12- and 18-month-old animals compared to their age-matched controls. There was also a correlation between changes in T1rho and the age of the animals.
  
  
  CONCLUSIONS
  T1rho relaxometry may be a sensitive method for noninvasively determining AD-related pathology in APP/PS1 mice.
authors.affiliation: Metabolic Magnetic Resonance Research & Computing Center (MMRRCC), Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6100, USA. ari@mail.mmrrcc.upenn.edu
authors.forename: Arijitt
authors.initials: A
authors.lastname: Borthakur
authors.forename: Tamar
authors.initials: T
authors.lastname: Gur
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Wheaton
authors.forename: Matthew
authors.initials: M
authors.lastname: Corbo
authors.forename: John Q
authors.initials: JQ
authors.lastname: Trojanowski
authors.forename: Virginia M-Y
authors.initials: VM
authors.lastname: Lee
authors.forename: Ravinder
authors.initials: R
authors.lastname: Reddy
mesh_terms: D000544:Alzheimer Disease / Q000473:pathology*; D000818:Animals; D004195:Disease Models, Animal; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008822:Mice, Transgenic; D058225:Plaque, Amyloid / Q000473:pathology*; D012720:Severity of Illness Index