Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2006 Feb 28;103(9):3410-5. Epub 2006 Feb 21.

AMPA receptor downscaling at the onset of Alzheimer's disease pathology in double knockin mice.

Author information

1
Center for Neural Science, New York University, NY 10003, USA.

Abstract

It is widely thought that Alzheimer's disease (AD) begins as a malfunction of synapses, eventually leading to cognitive impairment and dementia. Homeostatic synaptic scaling is a mechanism that could be crucial at the onset of AD but has not been examined experimentally. In this process, the synaptic strength of a neuron is modified so that the overall excitability of the cell is maintained. Here, we investigate whether synaptic scaling mediated by l-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) contributes to pathology in double knockin (2 x KI) mice carrying human mutations in the genes for amyloid precursor protein and presenilin-1. By using whole-cell recordings, we show that 2 x KI mice exhibit age-related downscaling of AMPAR-mediated evoked currents and spontaneous, miniature currents. Electron microscopic analysis further corroborates the synaptic AMPAR decrease. Additionally, 2 x KI mice show age-related deficits in bidirectional plasticity (long-term potentiation and long-term depression) and memory flexibility. These results suggest that AMPARs are important synaptic targets for AD and provide evidence that cognitive impairment may involve downscaling of postsynaptic AMPAR function.

PMID:
16492745
PMCID:
PMC1413872
DOI:
10.1073/pnas.0507313103
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center