QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, December 3, 2008, 28(49):13139-13149; doi:10.1523/JNEUROSCI.2932-08.2008

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Related articles in J. Neurosci. Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Scott, R. Articles by Rusakov, D. A. Search for Related Content PubMed PubMed Citation Articles by Scott, R. Articles by Rusakov, D. A.

 Previous Article  |  Next Article 

Cellular/Molecular
Target-Cell Specificity of Kainate Autoreceptor and Ca²⁺-Store-Dependent Short-Term Plasticity at Hippocampal Mossy Fiber Synapses

Ricardo Scott,¹ Tatjana Lalic,² Dimitri M. Kullmann,¹ Marco Capogna,² and Dmitri A. Rusakov¹

¹Institute of Neurology, University College London, London WC1N 3BG, United Kingdom, and ²Medical Research Council Anatomical Neuropharmacology Unit, Oxford OX1 3TH, United Kingdom

Correspondence should be addressed to either of the following: Dmitri A. Rusakov or Ricardo Scott, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK. Email: d.rusakov{at}ion.ucl.ac.uk or Email: r.scott{at}ion.ucl.ac.uk

Presynaptic kainate receptors (KARs) modulate transmission between dentate granule cells and CA3 pyramidal neurons. Whether presynaptic KARs affect other synapses made by granule cell axons [mossy fibers (MFs)], on hilar mossy cells or interneurons, is not known. Nor is it known whether glutamate release from a single MF is sufficient to activate these receptors. Here, we monitor Ca²⁺ in identified MF boutons traced from granule cell bodies. We show that a single action potential in a single MF activates both presynaptic KARs and Ca²⁺ stores, contributing to use-dependent facilitation at MF–CA3 pyramidal cell synapses. Rapid local application of kainate to the giant MF bouton has no detectable effect on the resting Ca²⁺ but facilitates action-potential-evoked Ca²⁺ entry through a Ca²⁺ store-dependent mechanism. Localized two-photon uncaging of the Ca²⁺ store receptor ligand IP₃ directly confirms the presence of functional Ca²⁺ stores at these boutons. In contrast, presynaptic Ca²⁺ kinetics at MF synapses on interneurons or mossy cells are insensitive to KAR blockade, to local kainate application or to photolytic release of IP₃. Consistent with this, postsynaptic responses evoked by activation of a single MF show KAR-dependent paired-pulse facilitation in CA3 pyramidal cells, but not in interneurons or mossy cells. Thus, KAR–Ca²⁺ store coupling acts as a synapse-specific, short-range autoreceptor mechanism.

Key words: synaptic plasticity; calcium [Ca]; presynaptic facilitation; kainic acid; Ca²⁺-induced Ca²⁺ release; granule cell; hippocampus

---

Received June 25, 2008; revised Oct. 9, 2008; accepted Oct. 17, 2008.

Correspondence should be addressed to either of the following: Dmitri A. Rusakov or Ricardo Scott, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK. Email: d.rusakov{at}ion.ucl.ac.uk or Email: r.scott{at}ion.ucl.ac.uk

Related articles in J. Neurosci.:

Role of Kainate Autoreceptors in Short-Term Plasticity at Hippocampal Mossy Fiber Synapses

Sheila L. Dargan and Mascia Amici
J. Neurosci. 2009 29: 5713-5715. [Full Text]  

This article has been cited by other articles:

				S. L. Dargan and M. Amici Role of Kainate Autoreceptors in Short-Term Plasticity at Hippocampal Mossy Fiber Synapses J. Neurosci., May 6, 2009; 29(18): 5713 - 5715. [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help