Extracellular calcium depletion as a mechanism of short-term synaptic depression

Citation
Rd. King et al., Extracellular calcium depletion as a mechanism of short-term synaptic depression, J NEUROPHYS, 85(5), 2001, pp. 1952-1959
Citations number
53
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF NEUROPHYSIOLOGY
ISSN journal
00223077 → ACNP
Volume
85
Issue
5
Year of publication
2001
Pages
1952 - 1959
Database
ISI
SICI code
0022-3077(200105)85:5<1952:ECDAAM>2.0.ZU;2-Z
Abstract
Recent experiments have demonstrated that normal neural activity can cause significant decrements in external calcium levels, and that these decrement s mediate a form of short-term synaptic depression. These findings raise th e possibility that certain forms of short-term synaptic depression at gluta matergic synapses throughout the mammalian CNS may be influenced by similar changes in external calcium. We use a computational model of the extracell ular space, combined with experimental data on calcium consumption, to show that such short-term depression can be accounted for by changes in calcium just outside active synapses, provided that external calcium diffusion is restricted. Remarkably, the model suggests the novel possibility that synap ses may possess private pools of external calcium that enforce some forms o f short-term depression in a synapse-specific manner.