Browse > Article

Increases in Effective Cleft Glutamate Concentration During Expression of LTP  

Jung, Su-Hyun (Department of Neuroscience, Ewha Institute of Neuroscience (EIN), School of Medicine, Ewha Womans University)
Choi, Suk-Woo (Department of Neuroscience, Ewha Institute of Neuroscience (EIN), School of Medicine, Ewha Womans University)
Publication Information
The Korean Journal of Physiology and Pharmacology / v.6, no.2, 2002 , pp. 113-119 More about this Journal
Abstract
Long-term potentiation (LTP) at hippocampal CA3-CA1 synapses is often associated with increases in quantal size, traditionally attributed to enhanced availability or efficacy of postsynaptic glutamate receptors. However, augmented quantal size might also reflect increases in neurotransmitter concentration within the synaptic cleft since AMPA-type glutamate receptors are not generally saturated during basal transmission. Here we report evidence that peak cleft glutamate concentration $([glu]_{cleft})$ increases during LTP, as indicated by a lessening of the blocking effects of rapidly unbinding antagonists of AMPA. The efficacy of slowly equilibrating antagonists remained unchanged. The elevated $[glu]_{cleft}$ helps support the increased quantal amplitude of AMPA-type EPSCs (excitatory postsynaptic currents) during LTP.
Keywords
Synapse; Glutamate; LTP; EPSC; Quantal size;
Citations & Related Records

Times Cited By SCOPUS : 0
연도 인용수 순위
  • Reference
1 Bekkers JM, Stevens CF. Presynaptic mechanism for long-term potentiation in the hippocampus. Nature 346: 724-729, 1990   DOI   ScienceOn
2 Bolshakov VY, Siegelbaum SA. Regulation of hippocampal transmitter release during development and long-term potentiation. Science 269: 1730-1734, 1995   DOI   ScienceOn
3 Kullmann DM, Asztely F. Extrasynaptic glutamate spillover in the hippocampus: evidence and implications. Trends Neurosci 21: 8 -14, 1998   DOI   ScienceOn
4 Larkman AU, Jack JJB. Synaptic plasticity: hippocampal LTP. Curr Opin Neurobiol 5: 324-334, 1995   DOI   ScienceOn
5 Shirke AM, Malinow R. Mechanisms of potentiation by calciumcalmodulin kinase II of postsynaptic sensitivity in rat hippocampal CA1 neurons. J Neurophysiol 78: 2682-2692, 1997   DOI
6 Bliss TVP, Collingridge GL. A synaptic model of memory: long-term potentiation in the hippocampus. Nature 361: 31-39, 1993   DOI   ScienceOn
7 Diamond JS, Jahr CE. Transporters buffer synaptically released glutamate on a submillisecond time scale. J Neurosci 17: 4672- 4687, 1997
8 Isaac JT, Nicoll RA, Malenka RC. Evidence for silent synapses: implications for the expression of LTP. Neuron 15: 427-434, 1995   DOI   ScienceOn
9 Katz B. The Release of Neural Transmitter Substances (Liverpool: Liverpool University Press) 1969
10 Clements JD, Lester RA, Tong G, Jahr CE, Westbrook GL. The time course of glutamate in the synaptic cleft. Science 258: 1498 -1501, 1992   DOI   ScienceOn
11 Clements JD, Feltz A, Sahara S, Westbrook GL. Activation kinetics of AMPA receptor channels reveal the number of functional agonist binding sites. J Neurosci 18: 119-127, 1998   PUBMED
12 Barria A, Muller D, Derkach V, Griffith LC, Soderling TR. Regulatory phosphrylation of AMPA-type glutamate receptors by CaM-KII during long-term potentiation. Science 276: 2042- 2045, 1997   DOI   ScienceOn
13 Perkel DJ, Nicoll RA. Evidence for all-or-none regulation of neurotransmitter release: implications for long-term potentiation. J Physiol Lond 471: 481-500, 1993   DOI
14 Silver RA, Cull-Candy SG, Takahashi T. Non-NMDA glutamate receptor occupancy and open probability at a rat cerebellar synapse with single and multiple release sites. J Physiol Lond 494: 231-250, 1996   DOI
15 Malgaroli A, Tsien RW. Glutamate-induced long-term potentiation of the frequency of miniature synaptic currents in cultured hippocampal neurons. Nature 357: 134-139, 1992   DOI   ScienceOn
16 Xie X, Liaw J-S, Baudry M, Berger TW. Novel expression mechanism for synaptic potentiation: Alignment of presynaptic release site and postsynaptic receptor. Proc Natl Acad Sci USA 94: 6983 -6988, 1997   DOI   ScienceOn
17 Kruk PJ, Korn H, Faber DS. The effects of geometrical parameters on synaptic transmission: a Monte Carlo simulation study. Biophys J 73: 2874-2890, 1997   DOI   ScienceOn
18 Wahl LM, Pouzat C, Stratford KJ. Monte Carlo simulation of fast excitatory synaptic transmission at a hippocampal synapse. J Neurophysiol 75: 597-608, 1996   DOI
19 Liu G, Choi S, Tsien RW. Variability of neurotransmitter concentration and nonsaturation of postsynaptic AMPA receptors at synapses in hippocampal cultures and slices. Neuron 22: 395- 409, 1999   DOI   ScienceOn
20 Tong G, Jahr CE. Multivesicular release from excitatory synapses of cultured hippocampal neurons. Neuron 12: 51-59, 1994   DOI   ScienceOn
21 Shi SH, Hayashi Y, Petralia RS, Zaman SH, Wenthold RJ, Svoboda K, Malinow R. Rapid spine delivery and redistribution of AMPA receptors after synaptic NMDA receptor activation. Science 284: 1811-1816, 1999   DOI   ScienceOn
22 Luhl A, Laurent JP, Figurov A, Muller D, Schachner M. Hippocampal long-term potentiation and neural cell adhesion molecules L1 and NCAM. Nature 372: 777-779, 1994   DOI   ScienceOn
23 Stevens CF, Wang Y. Changes in reliability of synaptic function as a mechanism for plasticity. Nature 371: 704-707, 1994   DOI   ScienceOn
24 Stricker AC, Field AC, Redman SJ. Changes in quantal parameters of EPSCs in rat CA1 neurons in vitro after the induction of long-term potentiation. J Physiol Lond 490: 443-454, 1996   DOI
25 Durand GM, Kovalchuk Y, Konnerth A. Long-term potentiation and functional synapse induction in developing hippocampus. Nature 381: 71-75, 1996   DOI   ScienceOn
26 Tang CM, Margulis M, Shi QY, Fielding A. Saturation of postynaptic glutamate receptors after quantal release of transmitter. Neuron 13: 1385-1393, 1994   DOI   ScienceOn
27 Kullmann DM, Nicoll RA. Long-term potentiation is associated with increases in quantal content and quantal amplitude. Nature 357: 240-244, 1992   DOI   ScienceOn
28 Lledo PM, Hjelmstad GO, Mukherji S, Soderling TR, Malenka RC, Nicoll RA. Calcium/calmodulin-dependent kinase II and longterm potentiation enhance synaptic transmission by the same mechanism. Proc Natl Acad Sci USA 92: 11175-11179, 1995   DOI   ScienceOn
29 Bergles DE, Jahr CE. Synaptic activation of glutamate transporters in hippocampal astrocytes. Neuron 19: 1297-1308, 1997   DOI   ScienceOn
30 Liao D, Hessler NA, Malinow R. Activation of postsynaptically silent synapses during pairing-induced LTP in CA1 region of hippocampal slice. Nature 375: 400-404, 1995   DOI   ScienceOn
31 Malinow R, Tsien RW. Presynaptic enhancement shown by wholecell recordings of long-term potentiation in hippocampal slices. Nature 346: 177-180, 1990   DOI   ScienceOn
32 Nicoll RA, Malenka RC. Contrasting properties of two forms of longterm potentiation in the hippocampus. Nature 377: 115-118, 1995   DOI   ScienceOn
33 Frerking M, Wilson M. Saturation of postsynaptic receptors at central synapses? Curr Opin Neurobiol 6: 395-403, 1996   DOI   ScienceOn
34 Rahamimoff R, Fernandez JM. Pre- and postfusion regulation of transmitter release. Neuron 18: 17-27, 1997   DOI   ScienceOn