The Journal of Neuroscience, April 11, 2007, 27(15):3987-3993; doi:10.1523/JNEUROSCI.5182-06.2007
Previous Article | Next Article 
Cellular/Molecular
Short-Term Plasticity of Kainate Receptor-Mediated EPSCs Induced by NMDA Receptors at Hippocampal Mossy Fiber Synapses
Nelson Rebola,1,2
Shankar Sachidhanandam,1
David Perrais,1
Rodrigo A. Cunha,2 and
Christophe Mulle1
1Laboratoire "Physiologie Cellulaire de la Synapse," Centre National de la Recherche Scientifique Unité Mixte de Recherche 5091, Bordeaux Neuroscience Institute, University of Bordeaux 2, 33077 Bordeaux, France, and 2Faculty of Medicine, Institute of Biochemistry, Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, 3004-504 Coimbra, Portugal
Correspondence should be addressed to Christophe Mulle at the above address. Email: mulle{at}u-bordeaux2.fr
Kainate receptors (KARs) are heteromeric ionotropic glutamate receptors that play a variety of functions in the regulation of the activity of synaptic networks. Little is known about the regulation of the function of synaptic KARs in the brain. In the present study, we found that a conditioning activation of synaptic NMDA receptors (NMDARs) induces short-term depression of KAREPSCs but not of AMPA receptorEPSCs at synapses between mossy fibers and CA3 pyramidal cells. Short-term depression of KAREPSCs by synaptic NMDARs peaked at 1 s and reversed within 20 s, was likely induced and expressed postsynaptically, and was homosynaptic. It depended on a rise of Ca2+ in the postsynaptic cell and on the activation of the phosphatase calcineurin that likely binds to the GluR6b (glutamate receptor subunit 6b) subunit splice variant allowing the dephosphorylation of KARs and inhibition of activity. Finally, we show in the current-clamp mode that short-term depression of KAREPSPs is induced by the coincident discharge of action potentials in the postsynaptic cell together with synaptic stimulation. Hence, this study describes a form of short-term synaptic plasticity that is postsynaptic, depends on the temporal order of presynaptic and postsynaptic spiking, and likely affects the summation properties of mossy fiber EPSPs.
Key words: kainate receptors; short-term synaptic plasticity; NMDA receptors; mossy fiber; hippocampus
Received Aug. 7, 2006;
revised Feb. 12, 2007;
accepted Feb. 15, 2007.
Correspondence should be addressed to Christophe Mulle at the above address. Email: mulle{at}u-bordeaux2.fr
This article has been cited by other articles:

|
 |

|
 |
 
S. Sachidhanandam, C. Blanchet, Y. Jeantet, Y. H. Cho, and C. Mulle
Kainate Receptors Act as Conditional Amplifiers of Spike Transmission at Hippocampal Mossy Fiber Synapses
J. Neurosci.,
April 15, 2009;
29(15):
5000 - 5008.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Miyata and K. Imoto
Contrary roles of kainate receptors in transmitter release at corticothalamic synapses onto thalamic relay and reticular neurons
J. Physiol.,
March 1, 2009;
587(5):
999 - 1012.
[Abstract]
[Full Text]
[PDF]
|
 |
|