Reduction of choline acetyltransferase activities inAPP 770 transgenic mice

Transgenic mice overexpressing the 770-amino acid isoform of human Alzheimer amyloid precursor protein exhibit extracellular β-amyloid deposits in brain regions including cerebral cortex and hippocampus, which are severely affected in Alzheimer’s disease patients. Significant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical and hippocampal brain regions in the transgenic mice at the age of 10 months compared with the age-matched non-transgenic mice, but such changes have not been observed in any brain regions of the transgenic mice under the age of 5 months. These results suggest that deposition of β-amyloid can induce changes in the brain cholinergic system of the transgenic mice.