In vivo measurement of plaque burden in a mouse model of Alzheimer's disease

Purpose: To demonstrate an MRI method for directly visualizing amyloid-beta (A beta) plaques in the APP/PS1 transgenic (tg) mouse brain in vivo, and show that T-1p relaxation rate increases progressively with Alzheimer's disease (AD)-related pathology in the tg mouse brain. Materials and Methods: We obtained in vivo MR images of a mouse model of AD (APP/PS1) that overexpres ses human amyloid precursor protein, and measured T-1p via quantitative relaxometric maps. Results: A significant decrease in T-1p 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 T-1p and the age of the ahimals. Conclusion: T-1p relaxometry may be a sensitive method for noninvasively determining AD-related pathology in API/PS1 mice.