Abstract |
The 22q11 deletion syndrome (22q11DS) is characterized by cognitive decline and increased risk of psychiatric disorders, mainly schizophrenia. The molecular mechanisms of neuronal dysfunction in cognitive symptoms of 22q11DS are poorly understood. Here, we report that a mouse model of 22q11DS, the Df(16)1/+ mouse, exhibits substantially enhanced short- and long-term synaptic plasticity at hippocampal CA3-CA1 synapses, which coincides with deficits in hippocampus-dependent spatial memory. These changes are evident in mature but not young animals. Electrophysiological, two-photon imaging and glutamate uncaging, and electron microscopic assays in acute brain slices showed that enhanced neurotransmitter release but not altered postsynaptic function or structure caused these changes. Enhanced neurotransmitter release in Df(16)1/+ mice coincided with altered calcium kinetics in CA3 presynaptic terminals and upregulated sarco(endo)plasmic reticulum calcium-ATPase type 2 (SERCA2). SERCA inhibitors rescued synaptic phenotypes of Df(16)1/+ mice. Thus, presynaptic SERCA2 upregulation may be a pathogenic event contributing to the cognitive symptoms of 22q11DS.
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Authors | Laurie R Earls, Ildar T Bayazitov, Robert G Fricke, Raymond B Berry, Elizabeth Illingworth, Guy Mittleman, Stanislav S Zakharenko |
Journal | The Journal of neuroscience : the official journal of the Society for Neuroscience
(J Neurosci)
Vol. 30
Issue 47
Pg. 15843-55
(Nov 24 2010)
ISSN: 1529-2401 [Electronic] United States |
PMID | 21106823
(Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
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Chemical References |
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Topics |
- 22q11 Deletion Syndrome
(genetics, metabolism, physiopathology)
- Animals
- Calcium
(metabolism)
- Disease Models, Animal
- Female
- Hippocampus
(pathology, physiology)
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Neuronal Plasticity
(genetics)
- Presynaptic Terminals
(pathology, physiology)
- Synaptic Transmission
(genetics)
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