HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 573/2/371    most recent jphysiol.2005.102723v1 Services Email this article to a friend Similar articles in this journal 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 Google Scholar Google Scholar Articles by Gebhardt, C. Articles by Cull-Candy, S. G. Search for Related Content PubMed PubMed Citation Articles by Gebhardt, C. Articles by Cull-Candy, S. G. Related Collections Neuroscience

¹ Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK

We have determined the functional properties of single AMPA receptor (AMPAR) and kainate receptor channels present in CA1 cells in hippocampal slices, to shed light on the relationship between single-channel behaviour and synaptic currents in these cells. To derive basic properties of AMPA and kainate channels activated by their excitatory transmitter, we examined outside-out patches exposed to glutamate. The kainate agonist SYM 2081, was used to confirm the presence of kainate receptors. Channels activated by glutamate or SYM 2081 exhibited conductance levels of 2–20 pS. Properties of single channels depended on the glutamate or AMPA concentration used. We observed a marked increase in mean channel conductance () from = 6.9, to 11.2 pS, when glutamate was increased from 10 µM to 10 mM. The kinetic behaviour of AMPAR channels was also influenced by agonist concentration, with an increase in ‘bursty’ events at higher concentrations. In contrast, kainate channels were characterized by brief openings without bursts. Consistent with the view that ‘bursty’ events arose from AMPARs, these openings decreased in the presence of the AMPAR blocker GYKI 53655. Furthermore, our experiments revealed a concentration-dependent increase in the number of conductance states during an individual AMPAR opening; AMPAR channels displayed up to four distinct levels. Our results are consistent with the view that the AMPAR channel conductance depends on the number of transmitter molecules bound in CA1 cells. We consider the implications of these findings for the change in EPSC properties during long-term potentiation (LTP).

(Received 30 November 2005; accepted after revision 28 February 2006; first published online 9 March 2006)
Corresponding author S. G. Cull-Candy: Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK. Email: s.cull-candy{at}ucl.ac.uk

This article has been cited by other articles:

				T. J. Wilding, E. Fulling, Y. Zhou, and J. E. Huettner Amino Acid Substitutions in the Pore Helix of GluR6 Control Inhibition by Membrane Fatty Acids J. Gen. Physiol., June 30, 2008; 132(1): 85 - 99. [Abstract] [Full Text] [PDF]

				E. S. Guire, M. C. Oh, T. R. Soderling, and V. A. Derkach Recruitment of Calcium-Permeable AMPA Receptors during Synaptic Potentiation Is Regulated by CaM-Kinase I J. Neurosci., June 4, 2008; 28(23): 6000 - 6009. [Abstract] [Full Text] [PDF]

				W. Zhang, Y. Cho, E. Lolis, and J. R. Howe Structural and Single-Channel Results Indicate That the Rates of Ligand Binding Domain Closing and Opening Directly Impact AMPA Receptor Gating J. Neurosci., January 23, 2008; 28(4): 932 - 943. [Abstract] [Full Text] [PDF]

				M. Postlethwaite, M. H. Hennig, J. R. Steinert, B. P. Graham, and I. D. Forsythe Acceleration of AMPA receptor kinetics underlies temperature-dependent changes in synaptic strength at the rat calyx of Held J. Physiol., February 15, 2007; 579(1): 69 - 84. [Abstract] [Full Text] [PDF]