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Philosophical Transactions of the Royal Society B: Biological Sciences logoLink to Philosophical Transactions of the Royal Society B: Biological Sciences
. 2003 Apr 29;358(1432):695–705. doi: 10.1098/rstb.2002.1249

Fusion pore modulation as a presynaptic mechanism contributing to expression of long-term potentiation.

Sukwoo Choi 1, Jürgen Klingauf 1, Richard W Tsien 1
PMCID: PMC1693158  PMID: 12740115

Abstract

Working on the idea that postsynaptic and presynaptic mechanisms of long-term potentiation (LTP) expression are not inherently mutually exclusive, we have looked for the existence and functionality of presynaptic mechanisms for augmenting transmitter release in hippocampal slices. Specifically, we asked if changes in glutamate release might contribute to the conversion of 'silent synapses' that show N-methyl-D-aspartate (NMDA) responses but no detectable alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) responses, to ones that exhibit both. Here, we review experiments where NMDA receptor responses provided a bioassay of cleft glutamate concentration, using opposition between peak [glu](cleft )and a rapidly reversible antagonist, L-AP5. We discuss findings of a dramatic increase in peak [glu](cleft) upon expression of pairing-induced LTP (Choi). We present simulations with a quantitative model of glutamatergic synaptic transmission that includes modulation of the presynaptic fusion pore, realistic cleft geometry and a distributed array of postsynaptic receptors and glutamate transporters. The modelling supports the idea that changes in the dynamics of glutamate release can contribute to synaptic unsilencing. We review direct evidence from Renger et al., in accord with the modelling, that trading off the strength and duration of the glutamate transient can markedly alter AMPA receptor responses with little effect on NMDA receptor responses. An array of additional findings relevant to fusion pore modulation and its proposed contribution to LTP expression are considered.

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Selected References

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  1. Bliss T. V., Collingridge G. L. A synaptic model of memory: long-term potentiation in the hippocampus. Nature. 1993 Jan 7;361(6407):31–39. doi: 10.1038/361031a0. [DOI] [PubMed] [Google Scholar]
  2. Bruns D., Jahn R. Real-time measurement of transmitter release from single synaptic vesicles. Nature. 1995 Sep 7;377(6544):62–65. doi: 10.1038/377062a0. [DOI] [PubMed] [Google Scholar]
  3. Choi S., Klingauf J., Tsien R. W. Postfusional regulation of cleft glutamate concentration during LTP at 'silent synapses'. Nat Neurosci. 2000 Apr;3(4):330–336. doi: 10.1038/73895. [DOI] [PubMed] [Google Scholar]
  4. Clements J. D., Lester R. A., Tong G., Jahr C. E., Westbrook G. L. The time course of glutamate in the synaptic cleft. Science. 1992 Nov 27;258(5087):1498–1501. doi: 10.1126/science.1359647. [DOI] [PubMed] [Google Scholar]
  5. Clements J. D. Transmitter timecourse in the synaptic cleft: its role in central synaptic function. Trends Neurosci. 1996 May;19(5):163–171. doi: 10.1016/s0166-2236(96)10024-2. [DOI] [PubMed] [Google Scholar]
  6. Clements J. D., Westbrook G. L. Activation kinetics reveal the number of glutamate and glycine binding sites on the N-methyl-D-aspartate receptor. Neuron. 1991 Oct;7(4):605–613. doi: 10.1016/0896-6273(91)90373-8. [DOI] [PubMed] [Google Scholar]
  7. Diamond J. S., Jahr C. E. Transporters buffer synaptically released glutamate on a submillisecond time scale. J Neurosci. 1997 Jun 15;17(12):4672–4687. doi: 10.1523/JNEUROSCI.17-12-04672.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Durand G. M., Kovalchuk Y., Konnerth A. Long-term potentiation and functional synapse induction in developing hippocampus. Nature. 1996 May 2;381(6577):71–75. doi: 10.1038/381071a0. [DOI] [PubMed] [Google Scholar]
  9. Emptage N., Bliss T. V., Fine A. Single synaptic events evoke NMDA receptor-mediated release of calcium from internal stores in hippocampal dendritic spines. Neuron. 1999 Jan;22(1):115–124. doi: 10.1016/s0896-6273(00)80683-2. [DOI] [PubMed] [Google Scholar]
  10. Fisher R. J., Pevsner J., Burgoyne R. D. Control of fusion pore dynamics during exocytosis by Munc18. Science. 2001 Feb 2;291(5505):875–878. doi: 10.1126/science.291.5505.875. [DOI] [PubMed] [Google Scholar]
  11. Gasparini S., Saviane C., Voronin L. L., Cherubini E. Silent synapses in the developing hippocampus: lack of functional AMPA receptors or low probability of glutamate release? Proc Natl Acad Sci U S A. 2000 Aug 15;97(17):9741–9746. doi: 10.1073/pnas.170032297. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Gomperts S. N., Rao A., Craig A. M., Malenka R. C., Nicoll R. A. Postsynaptically silent synapses in single neuron cultures. Neuron. 1998 Dec;21(6):1443–1451. doi: 10.1016/s0896-6273(00)80662-5. [DOI] [PubMed] [Google Scholar]
  13. Graham M. E., Fisher R. J., Burgoyne R. D. Measurement of exocytosis by amperometry in adrenal chromaffin cells: effects of clostridial neurotoxins and activation of protein kinase C on fusion pore kinetics. Biochimie. 2000 May;82(5):469–479. doi: 10.1016/s0300-9084(00)00196-6. [DOI] [PubMed] [Google Scholar]
  14. Hayashi Y., Shi S. H., Esteban J. A., Piccini A., Poncer J. C., Malinow R. Driving AMPA receptors into synapses by LTP and CaMKII: requirement for GluR1 and PDZ domain interaction. Science. 2000 Mar 24;287(5461):2262–2267. doi: 10.1126/science.287.5461.2262. [DOI] [PubMed] [Google Scholar]
  15. Isaac J. T., Nicoll R. A., Malenka R. C. Evidence for silent synapses: implications for the expression of LTP. Neuron. 1995 Aug;15(2):427–434. doi: 10.1016/0896-6273(95)90046-2. [DOI] [PubMed] [Google Scholar]
  16. Jonas P., Major G., Sakmann B. Quantal components of unitary EPSCs at the mossy fibre synapse on CA3 pyramidal cells of rat hippocampus. J Physiol. 1993 Dec;472:615–663. doi: 10.1113/jphysiol.1993.sp019965. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Jonas P., Sakmann B. Glutamate receptor channels in isolated patches from CA1 and CA3 pyramidal cells of rat hippocampal slices. J Physiol. 1992 Sep;455:143–171. doi: 10.1113/jphysiol.1992.sp019294. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Klyachko Vitaly A., Jackson Meyer B. Capacitance steps and fusion pores of small and large-dense-core vesicles in nerve terminals. Nature. 2002 Jul 4;418(6893):89–92. doi: 10.1038/nature00852. [DOI] [PubMed] [Google Scholar]
  19. Kullmann D. M., Asztely F. Extrasynaptic glutamate spillover in the hippocampus: evidence and implications. Trends Neurosci. 1998 Jan;21(1):8–14. doi: 10.1016/s0166-2236(97)01150-8. [DOI] [PubMed] [Google Scholar]
  20. Liao D., Hessler N. A., Malinow R. Activation of postsynaptically silent synapses during pairing-induced LTP in CA1 region of hippocampal slice. Nature. 1995 Jun 1;375(6530):400–404. doi: 10.1038/375400a0. [DOI] [PubMed] [Google Scholar]
  21. Liao D., Zhang X., O'Brien R., Ehlers M. D., Huganir R. L. Regulation of morphological postsynaptic silent synapses in developing hippocampal neurons. Nat Neurosci. 1999 Jan;2(1):37–43. doi: 10.1038/4540. [DOI] [PubMed] [Google Scholar]
  22. Liu G., Choi S., Tsien R. W. Variability of neurotransmitter concentration and nonsaturation of postsynaptic AMPA receptors at synapses in hippocampal cultures and slices. Neuron. 1999 Feb;22(2):395–409. doi: 10.1016/s0896-6273(00)81099-5. [DOI] [PubMed] [Google Scholar]
  23. Lollike K., Borregaard N., Lindau M. Capacitance flickers and pseudoflickers of small granules, measured in the cell-attached configuration. Biophys J. 1998 Jul;75(1):53–59. doi: 10.1016/S0006-3495(98)77494-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Magee J. C., Johnston D. A synaptically controlled, associative signal for Hebbian plasticity in hippocampal neurons. Science. 1997 Jan 10;275(5297):209–213. doi: 10.1126/science.275.5297.209. [DOI] [PubMed] [Google Scholar]
  25. Malgaroli A., Ting A. E., Wendland B., Bergamaschi A., Villa A., Tsien R. W., Scheller R. H. Presynaptic component of long-term potentiation visualized at individual hippocampal synapses. Science. 1995 Jun 16;268(5217):1624–1628. doi: 10.1126/science.7777862. [DOI] [PubMed] [Google Scholar]
  26. Malgaroli A., Tsien R. W. Glutamate-induced long-term potentiation of the frequency of miniature synaptic currents in cultured hippocampal neurons. Nature. 1992 May 14;357(6374):134–139. doi: 10.1038/357134a0. [DOI] [PubMed] [Google Scholar]
  27. Malinow R., Schulman H., Tsien R. W. Inhibition of postsynaptic PKC or CaMKII blocks induction but not expression of LTP. Science. 1989 Aug 25;245(4920):862–866. doi: 10.1126/science.2549638. [DOI] [PubMed] [Google Scholar]
  28. Malinow R., Tsien R. W. Presynaptic enhancement shown by whole-cell recordings of long-term potentiation in hippocampal slices. Nature. 1990 Jul 12;346(6280):177–180. doi: 10.1038/346177a0. [DOI] [PubMed] [Google Scholar]
  29. McAllister A. K., Stevens C. F. Nonsaturation of AMPA and NMDA receptors at hippocampal synapses. Proc Natl Acad Sci U S A. 2000 May 23;97(11):6173–6178. doi: 10.1073/pnas.100126497. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Montgomery J. M., Pavlidis P., Madison D. V. Pair recordings reveal all-silent synaptic connections and the postsynaptic expression of long-term potentiation. Neuron. 2001 Mar;29(3):691–701. doi: 10.1016/s0896-6273(01)00244-6. [DOI] [PubMed] [Google Scholar]
  31. Nusser Z., Lujan R., Laube G., Roberts J. D., Molnar E., Somogyi P. Cell type and pathway dependence of synaptic AMPA receptor number and variability in the hippocampus. Neuron. 1998 Sep;21(3):545–559. doi: 10.1016/s0896-6273(00)80565-6. [DOI] [PubMed] [Google Scholar]
  32. Oertner Thomas G., Sabatini Bernardo L., Nimchinsky Esther A., Svoboda Karel. Facilitation at single synapses probed with optical quantal analysis. Nat Neurosci. 2002 Jul;5(7):657–664. doi: 10.1038/nn867. [DOI] [PubMed] [Google Scholar]
  33. Olverman H. J., Jones A. W., Mewett K. N., Watkins J. C. Structure/activity relations of N-methyl-D-aspartate receptor ligands as studied by their inhibition of [3H]D-2-amino-5-phosphonopentanoic acid binding in rat brain membranes. Neuroscience. 1988 Jul;26(1):17–31. doi: 10.1016/0306-4522(88)90124-8. [DOI] [PubMed] [Google Scholar]
  34. Otmakhova N. A., Otmakhov N., Mortenson L. H., Lisman J. E. Inhibition of the cAMP pathway decreases early long-term potentiation at CA1 hippocampal synapses. J Neurosci. 2000 Jun 15;20(12):4446–4451. doi: 10.1523/JNEUROSCI.20-12-04446.2000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Pothos E. N., Davila V., Sulzer D. Presynaptic recording of quanta from midbrain dopamine neurons and modulation of the quantal size. J Neurosci. 1998 Jun 1;18(11):4106–4118. doi: 10.1523/JNEUROSCI.18-11-04106.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Pyle J. L., Kavalali E. T., Choi S., Tsien R. W. Visualization of synaptic activity in hippocampal slices with FM1-43 enabled by fluorescence quenching. Neuron. 1999 Dec;24(4):803–808. doi: 10.1016/s0896-6273(00)81028-4. [DOI] [PubMed] [Google Scholar]
  37. Raman I. M., Trussell L. O. The mechanism of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor desensitization after removal of glutamate. Biophys J. 1995 Jan;68(1):137–146. doi: 10.1016/S0006-3495(95)80168-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Renger J. J., Egles C., Liu G. A developmental switch in neurotransmitter flux enhances synaptic efficacy by affecting AMPA receptor activation. Neuron. 2001 Feb;29(2):469–484. doi: 10.1016/s0896-6273(01)00219-7. [DOI] [PubMed] [Google Scholar]
  39. Rosenmund C., Stern-Bach Y., Stevens C. F. The tetrameric structure of a glutamate receptor channel. Science. 1998 Jun 5;280(5369):1596–1599. doi: 10.1126/science.280.5369.1596. [DOI] [PubMed] [Google Scholar]
  40. Rusakov D. A., Kullmann D. M. Extrasynaptic glutamate diffusion in the hippocampus: ultrastructural constraints, uptake, and receptor activation. J Neurosci. 1998 May 1;18(9):3158–3170. doi: 10.1523/JNEUROSCI.18-09-03158.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Ryan T. A., Ziv N. E., Smith S. J. Potentiation of evoked vesicle turnover at individually resolved synaptic boutons. Neuron. 1996 Jul;17(1):125–134. doi: 10.1016/s0896-6273(00)80286-x. [DOI] [PubMed] [Google Scholar]
  42. Scepek S., Coorssen J. R., Lindau M. Fusion pore expansion in horse eosinophils is modulated by Ca2+ and protein kinase C via distinct mechanisms. EMBO J. 1998 Aug 3;17(15):4340–4345. doi: 10.1093/emboj/17.15.4340. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Shi S. H., Hayashi Y., Petralia R. S., Zaman S. H., Wenthold R. J., Svoboda K., Malinow R. Rapid spine delivery and redistribution of AMPA receptors after synaptic NMDA receptor activation. Science. 1999 Jun 11;284(5421):1811–1816. doi: 10.1126/science.284.5421.1811. [DOI] [PubMed] [Google Scholar]
  44. Shi S., Hayashi Y., Esteban J. A., Malinow R. Subunit-specific rules governing AMPA receptor trafficking to synapses in hippocampal pyramidal neurons. Cell. 2001 May 4;105(3):331–343. doi: 10.1016/s0092-8674(01)00321-x. [DOI] [PubMed] [Google Scholar]
  45. Spruce A. E., Breckenridge L. J., Lee A. K., Almers W. Properties of the fusion pore that forms during exocytosis of a mast cell secretory vesicle. Neuron. 1990 May;4(5):643–654. doi: 10.1016/0896-6273(90)90192-i. [DOI] [PubMed] [Google Scholar]
  46. Stanton P. K., Heinemann U., Muller W. FM1-43 imaging reveals cGMP-dependent long-term depression of presynaptic transmitter release. J Neurosci. 2001 Oct 1;21(19):RC167–RC167. doi: 10.1523/JNEUROSCI.21-19-j0002.2001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Stiles J. R., Van Helden D., Bartol T. M., Jr, Salpeter E. E., Salpeter M. M. Miniature endplate current rise times less than 100 microseconds from improved dual recordings can be modeled with passive acetylcholine diffusion from a synaptic vesicle. Proc Natl Acad Sci U S A. 1996 Jun 11;93(12):5747–5752. doi: 10.1073/pnas.93.12.5747. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Wadiche J. I., Kavanaugh M. P. Macroscopic and microscopic properties of a cloned glutamate transporter/chloride channel. J Neurosci. 1998 Oct 1;18(19):7650–7661. doi: 10.1523/JNEUROSCI.18-19-07650.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Zakharenko S. S., Zablow L., Siegelbaum S. A. Visualization of changes in presynaptic function during long-term synaptic plasticity. Nat Neurosci. 2001 Jul;4(7):711–717. doi: 10.1038/89498. [DOI] [PubMed] [Google Scholar]
  50. Zakharenko Stanislav S., Zablow Leonard, Siegelbaum Steven A. Altered presynaptic vesicle release and cycling during mGluR-dependent LTD. Neuron. 2002 Sep 12;35(6):1099–1110. doi: 10.1016/s0896-6273(02)00898-x. [DOI] [PubMed] [Google Scholar]
  51. Zhou Z., Misler S., Chow R. H. Rapid fluctuations in transmitter release from single vesicles in bovine adrenal chromaffin cells. Biophys J. 1996 Mar;70(3):1543–1552. doi: 10.1016/S0006-3495(96)79718-7. [DOI] [PMC free article] [PubMed] [Google Scholar]

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