Synaptic strengthening through activation of Ca2+-permeable AMPA receptors.
Postsynaptic Ca2+ elevation during synaptic transmission is an important trigger for short- and long-term changes in synaptic strength in the vertebrate central nervous system. The AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate) receptors, a subfamily of glutamate receptors, mediate much of the excitatory synaptic transmission in the brain and spinal cord. It has been shown that a subtype of the AMPA receptor is Ca2+-permeable and is present in the subpopulations of neurons. When synaptically localized, these receptors should mediate postsynaptic Ca2+ influx, providing a trigger for changes in synaptic strength. Here we show that Ca2+-permeable AMPA receptors are synaptically localized on a subpopulation of dorsal horn neurons, and that they provide a synaptically gated route of Ca2+ entry, and that activation of these receptors strengthens synaptic transmission mediated by AMPA receptors. This pathway for postsynaptic Ca2+ influx may provide a new form of activity-dependent modulation of synaptic strength.
Gu
J G
JG
Department of Physiology and Cellular Biophysics, Columbia University, New York, 10032, USA.
Albuquerque
C
C
Lee
C J
CJ
MacDermott
A B
AB
D000200:Action Potentials; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability; D002478:Cells, Cultured; D009474:Neurons / Q000378:metabolism*; D009997:Osmotic Pressure; D018091:Receptors, AMPA / Q000378:metabolism*; D013111:Spider Venoms / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000378:metabolism*
C044936:JSTX spider toxin; D018091:Receptors, AMPA; D013111:Spider Venoms; D002118:Calcium