Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Facilitation at single synapses probed with optical quantal analysis

Nature Neuroscience volume 5, pages 657–664 (2002)Cite this article

Abstract

Many synapses can change their strength rapidly in a use-dependent manner, but the mechanisms of such short-term plasticity remain unknown. To understand these mechanisms, measurements of neurotransmitter release at single synapses are required. We probed transmitter release by imaging transient increases in [Ca2+] mediated by synaptic N-methyl-D-aspartate receptors (NMDARs) in individual dendritic spines of CA1 pyramidal neurons in rat brain slices, enabling quantal analysis at single synapses. We found that changes in release probability, produced by paired-pulse facilitation (PPF) or by manipulation of presynaptic adenosine receptors, were associated with changes in glutamate concentration in the synaptic cleft, indicating that single synapses can release a variable amount of glutamate per action potential. The relationship between release probability and response size is consistent with a binomial model of vesicle release with several (>5) independent release sites per active zone, suggesting that multivesicular release contributes to facilitation at these synapses.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Measurement of NMDAR-mediated [Ca2+] transients in single spines.
Figure 2: Paired-pulse facilitation of excitatory postsynaptic currents.
Figure 3: Paired-pulse facilitation at a single synapse.
Figure 4: Dissecting PPF in individual synapses.
Figure 5: Varying release probability pharmacologically changes potency.
Figure 6: Rise times of [Ca2+] transients under control and potentiated conditions.
Figure 7: Change in potency is constant as a function of holding potential.

Similar content being viewed by others

References

  1. Katz, B. The Release of Neural Transmitter Substances (Thomas, Springfield, Illinois, 1969).

    Google Scholar 

  2. Harris, K.M. & Sultan, P. Variation in the number, location and size of synaptic vesicles provides an anatomical basis for the nonuniform probability of release at hippocampal CA1 synapses. Neuropharmacology 34, 1387–1395 (1995).

    Article  CAS  Google Scholar 

  3. Schikorski, T. & Stevens, C.F. Quantitative ultrastructural analysis of hippocampal excitatory synapses. J. Neurosci. 17, 5858–5867 (1997).

    Article  CAS  PubMed  Google Scholar 

  4. Dobrunz, L.E. & Stevens, C.F. Heterogeneity of release probability, facilitation, and depletion at central synapses. Neuron 18, 995–1008 (1997).

    Article  CAS  Google Scholar 

  5. Hanse, E. & Gustafsson, B. Quantal variability at glutamatergic synapses in area CA1 of the rat neonatal hippocampus. J. Physiol. 531, 467–480 (2001).

    Article  CAS  PubMed  Google Scholar 

  6. Auger, C., Kondo, S. & Marty, A. Multivesicular release at single functional synaptic sites in cerebellar stellate and basket cells. J. Neurosci. 18, 4532–4547 (1998).

    Article  CAS  Google Scholar 

  7. Tong, G. & Jahr, C.E. Multivesicular release from excitatory synapses of cultured hippocampal neurons. Neuron 12, 51–59 (1994).

    Article  CAS  Google Scholar 

  8. Isaac, J.T. et al. An investigation of the expression mechanism of LTP of AMPA receptor–mediated synaptic transmission at hippocampal CA1 synapses using failures analysis and dendritic recordings. Neuropharmacology 37, 1399–1410 (1998).

    Article  CAS  Google Scholar 

  9. Wadiche, J.I. & Jahr, C.E. Multivesicular release at climbing fiber-purkinje cell synapses. Neuron 32, 301–313 (2001).

    Article  CAS  Google Scholar 

  10. Stevens, C.F. & Wang, Y. Facilitation and depression at single central synapses. Neuron 14, 795–802 (1995).

    Article  CAS  Google Scholar 

  11. Redman, S. Quantal analysis of synaptic potentials in neurons of the central nervous system. Physiol. Rev. 70, 165–198 (1990).

    Article  CAS  Google Scholar 

  12. Regehr, W.G. & Stevens, C.F. in Synapses (eds. Cowan, W. M., Sudhof, T. C. & Stevens, C. F.) 135–175 (Johns Hopkins Univ. Press, Baltimore, 2001).

    Google Scholar 

  13. Auger, C. & Marty, A. Quantal currents at single-site central synapses. J. Physiol. 526, 3–11 (2000).

    Article  CAS  PubMed  Google Scholar 

  14. Korn, H., Triller, A., Mallet, A. & Faber, D.S. Fluctuating responses at a central synapse: n of binomial fit predicts number of stained presynaptic boutons. Science 213, 898–901 (1981).

    Article  CAS  Google Scholar 

  15. Spruston, N., Jonas, P. & Sakmann, B. Dendritic glutamate receptor channels in rat hippocampal CA3 and CA1 pyramidal neurons. J. Physiol. 482, 325–352 (1995).

    Article  CAS  PubMed  Google Scholar 

  16. Faber, D.S., Young, W.S., Legendre, P. & Korn, H. Intrinsic quantal variability due to stochastic properties of receptor–transmitter interactions. Science 258, 1494–1498 (1992).

    Article  CAS  Google Scholar 

  17. Magee, J.C. & Cook, E.P. Somatic EPSP amplitude is independent of synapse location in hippocampal pyramidal neurons. Nat. Neurosci. 3, 895–903 (2000).

    Article  CAS  Google Scholar 

  18. Stuart, G. & Spruston, N. Determinants of voltage attenuation in neocortical pyramidal neuron dendrites. J. Neurosci. 18, 3501–3510 (1998).

    Article  CAS  Google Scholar 

  19. Williams, S.R. & Stuart, G.J. Dependence of EPSP efficacy on synapse location in neocortical pyramidal neurons. Science 295, 1907–1910 (2002).

    Article  CAS  Google Scholar 

  20. Mainen, Z.F., Malinow, R. & Svoboda, K. Synaptic calcium transients in single spines indicate that NMDA receptors are not saturated. Nature 399, 151–155 (1999).

    Article  CAS  Google Scholar 

  21. Harris, K.M. & Stevens, J.K. Dendritic spines of CA1 pyramidal cells in the rat hippocampus: serial electron microscopy with reference to their biophysical characteristics. J. Neurosci. 9, 2982–2997 (1989).

    Article  CAS  Google Scholar 

  22. Yuste, R. & Denk, W. Dendritic spines as basic functional units of neuronal integration. Nature 375, 682–684 (1995).

    Article  CAS  Google Scholar 

  23. Denk, W. & Svoboda, K. Photon upmanship: why multiphoton imaging is more than a gimmick. Neuron 18, 351–357 (1997).

    Article  CAS  Google Scholar 

  24. McAllister, A.K. & Stevens, C.F. Nonsaturation of AMPA and NMDA receptors at hippocampal synapses. Proc. Natl. Acad. Sci. USA 97, 6173–6178 (2000).

    Article  CAS  Google Scholar 

  25. Umemiya, M., Senda, M. & Murphy, T.H. Behavior of NMDA and AMPA receptor-mediated miniature EPSCs at rat cortical neuron synapses identified by calcium imaging. J. Physiol. 521, 113–122 (1999).

    Article  CAS  PubMed  Google Scholar 

  26. Sabatini, B.L., Maravall, M. & Svoboda, K. Ca2+ signaling in dendritic spines. Curr. Opin. Neurobiol. 11, 349–356 (2001).

    Article  CAS  PubMed  Google Scholar 

  27. Mainen, Z.F. et al. Two-photon imaging in living brain slices. Methods 18, 231–239 (1999).

    Article  CAS  Google Scholar 

  28. Bekkers, J.M., Richerson, G.B. & Stevens, C.F. Origins of variability in quantal size in cultured hippocampal neurons and hippocampal slices. Proc. Natl. Acad. Sci. USA 87, 5359–5362 (1990).

    Article  CAS  Google Scholar 

  29. Zucker, R.S. & Regehr, W.G. Short-term synaptic plasticity. Annu. Rev. Neurosci. 12, 13–31 (1989).

    Article  CAS  Google Scholar 

  30. Wu, L.G. & Saggau, P. Adenosine inhibits evoked synaptic transmission primarily by reducing presynaptic calcium influx in area CA1 of hippocampus. Neuron 12, 1139–1148 (1994).

    Article  CAS  Google Scholar 

  31. Wu, L.G. & Saggau, P. Presynaptic inhibition of elicited neurotransmitter release. Trends Neurosci. 20, 204–212 (1997).

    Article  CAS  Google Scholar 

  32. Choi, S., Klingauf, J. & Tsien, R.W. Postfusional regulation of cleft glutamate concentration during LTP at 'silent synapses'. Nat. Neurosci. 3, 330–336 (2000).

    Article  CAS  Google Scholar 

  33. 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 7, 605–613 (1991).

    Article  CAS  Google Scholar 

  34. Neher, E. The use of Fura-2 for estimating Ca buffers and Ca fluxes. Neuropharmacology 34, 1423–1442 (1995).

    Article  CAS  Google Scholar 

  35. Sabatini, B.S., Oertner, T.G. & Svoboda, K. The life-cycle of Ca2+ ions in spines. Neuron 33, 439–452 (2002).

    Article  CAS  Google Scholar 

  36. Asztely, F., Erdemli, G. & Kullmann, D.M. Extrasynaptic glutamate spillover in the hippocampus: dependence on temperature and the role of active glutamate uptake. Neuron 18, 281–293 (1997).

    Article  CAS  Google Scholar 

  37. Arnth-Jensen, N., Jabaudon, D. & Scanziani, M. Cooperation between independent hippocampal synapses is controlled by glutamate uptake. Nat. Neurosci. 5, 325–331 (2002).

    Article  CAS  Google Scholar 

  38. Diamond, J.S. Neuronal glutamate transporters limit activation of NMDA receptors by neurotransmitter spillover on CA1 pyramidal cells. J. Neurosci. 21, 8328–8338 (2001).

    Article  CAS  Google Scholar 

  39. Barbour, B. An evaluation of synapse independence. J. Neurosci. 21, 7969–7984 (2001).

    Article  CAS  Google Scholar 

  40. Rusakov, D.A. & Kullmann, D.M. Extrasynaptic glutamate diffusion in the hippocampus: ultrastructural constraints, uptake, and receptor activation. J. Neurosci. 18, 3158–3170 (1998).

    Article  CAS  Google Scholar 

  41. Emptage, N., Bliss, T.V.P. & Fine, A. Single synaptic events evoke NMDA receptor-mediated release of calcium from internal stores in hippocampal dendritic spines. Neuron 22, 115–124 (1999).

    Article  CAS  Google Scholar 

  42. Kovalchuk, Y., Eilers, J., Lisman, J. & Konnerth, A. NMDA receptor–mediated subthreshold Ca2+ signals in spines of hippocampal neurons. J. Neurosci. 20, 1791–1799 (2000).

    Article  CAS  Google Scholar 

  43. Spacek, J. & Harris, K.M. Three-dimensional organization of smooth endoplasmic reticulum in hippocampal CA1 dendrites and dendritic spines of the immature and mature rat. J. Neurosci. 17, 190–203 (1997).

    Article  CAS  PubMed  Google Scholar 

  44. Patneau, D.K. & Mayer, M.L. Structure–activity relationships for amino acid transmitter candidates acting at N-methyl-D-aspartate and quisqualate receptors. J. Neurosci. 10, 2385–2399 (1990).

    Article  CAS  PubMed  Google Scholar 

  45. Bliss, T.V.P. & Collingridge, G.L. A synaptic model of memory: long-term potentiation in the hippocampus. Nature 361, 31–39 (1993).

    Article  CAS  Google Scholar 

  46. Renger, J.J., Egles, C. & Liu, G. A developmental switch in neurotransmitter flux enhances synaptic efficacy by affecting AMPA receptor activation. Neuron 29, 469–484 (2001).

    Article  CAS  Google Scholar 

  47. Liao, D., Hessler, N.A. & Malinow, R. Activation of postsynaptically silent synapses during pairing-induced LTP in CA1 region of hippocampal slice. Nature 375, 400–404 (1995).

    Article  CAS  Google Scholar 

  48. Isaac, J.T., Nicoll, R.A. & Malenka, R.C. Evidence for silent synapses: implications for the expression of LTP. Neuron 15, 427–434 (1995).

    Article  CAS  PubMed  Google Scholar 

  49. Sabatini, B.L. & Svoboda, K. Analsyis of calcium channels in single spines using optical fluctuation analysis. Nature 408, 589–593 (2000).

    Article  CAS  PubMed  Google Scholar 

  50. Sather, W., Dieudonne, S., MacDonald, J.F. & Ascher, P. Activation and desensitization of N-methyl-D-aspartate receptors in nucleated outside-out patches from mouse neurons. J. Physiol. 450, 643–672 (1992).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

We thank Z. Mainen, R. Malinow, M. Maravall and R. Yasuda for comments on the manuscript, and T. Pologruto for software development. This work was supported by grants from the Swartz Initiative for Computational Neuroscience (to T.G.O.), the Helen Hay Whitney Foundation (to B.L.S.), the Pew and Mathers Foundations and the National Institutes of Health (NIH).

Author information

Authors and Affiliations

  1. Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, 11724, New York, USA

    Thomas G. Oertner, Bernardo L. Sabatini, Esther A. Nimchinsky & Karel Svoboda

Authors
  1. Thomas G. Oertner
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Bernardo L. Sabatini
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Esther A. Nimchinsky
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Karel Svoboda
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Karel Svoboda.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Oertner, T., Sabatini, B., Nimchinsky, E. et al. Facilitation at single synapses probed with optical quantal analysis. Nat Neurosci 5, 657–664 (2002). https://doi.org/10.1038/nn867

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nn867

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing