Summary
The functional properties of central synapses are difficult to study because they can be modulated either presynaptically or postsynaptically, each connection has multiple contacts and release at each contact is stochastic. Moreover, studying central synapses with electrophysiology is complicated by the fact that synapses are often remote from the recording site and signals are often difficult to resolve above the noise. This together with the fact that central synapses often have few release sites and have nonuniform quantal parameters makes classical quantal analysis methods difficult to apply. Here, we discuss an alternative approach, multiple-probability fluctuation analysis (MPFA), which can be used to estimate nonuniform quantal parameters from fits of the relationship between the variance and mean amplitude of postsynaptic responses, recorded at different release probabilities. We illustrate the experimental protocols and the analysis procedure that should be followed to perform MPFA and interpret the estimated parameters.
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References
del Castillo, J., and Katz, B. (1954) Quantal components of the end-plate potential. J. Physiol. 124, 560–573.
Katz, B. (1969) The Release of Neural Transmitter Substances, Liverpool University Press, Liverpool, UK.
Vere-Jones, D. (1966) Simple stochastic models for the release of quanta of transmitter from a nerve terminal. Aust. J. Stat. 8, 53–63.
Walmsley, B. (1995) Interpretation of “quantal” peaks in distributions of evoked synaptic transmission at central synapses. Proc. R. Soc. Lond. B Biol. Sci. 261, 245–250.
Heinemann, S. H., and Conti, F. (1992) Nonstationary noise analysis and application to patch clamp recordings. Methods Enzymol. 207, 131–148.
Sigworth, F. J. (1980) The variance of sodium current fluctuations at the node of Ranvier. J. Physiol. 307, 97–129.
Reid, C. A., and Clements, J. D. (1999) Postsynaptic expression of long-term potentiation in the rat dentate gyrus demonstrated by variance-mean analysis. J. Physiol. 518, 121–130.
Silver, R. A., Momiyama, A., and Cull-Candy, S. G. (1998) Locus of frequency-dependent depression identified with multiple-probability fluctuation analysis at rat climbing fibre-Purkinje cell synapses. J. Physiol. 510, 881–902.
Meyer, A. C., Neher, E., and Schneggenburger, R. (2001) Estimation of quantal size and number of functional active zones at the calyx of held synapse by nonstationary EPSC variance analysis. J. Neurosci. 21, 7889–7900.
Scheuss, V., and Neher, E. (2001) Estimating synaptic parameters from mean, variance, and covariance in trains of synaptic responses. Biophys. J. 81, 1970–1989.
Neher, E., and Sakaba, T. (2001) Estimating transmitter release rates from postsynaptic current fluctuations. J. Neurosci. 21, 9638–9654.
Clements, J. D., and Silver, R. A. (2000) Unveiling synaptic plasticity: a new graphical and analytical approach. Trends Neurosci. 23, 105–113.
Silver, R. A. (2003) Estimation of nonuniform quantal parameters with multiple-probability fluctuation analysis: theory, application and limitations. J. Neurosci. Methods 130, 127–141.
Frerking, M., and Wilson, M. (1996) Effects of variance in mini amplitude on stimulus-evoked release: a comparison of two models. Biophys. J. 70, 2078–2091.
Walmsley, B., Edwards, F. R., and Tracey, D. J. (1988) Nonuniform release probabilities underlie quantal synaptic transmission at a mammalian excitatory central synapse. J. Neurophysiol. 60, 889–908.
Murthy, V. N., Sejnowski, T. J., and Stevens, C. F. (1997) Heterogeneous release properties of visualized individual hippocampal synapses. Neuron 18, 599–612.
Saviane, C., and Silver, R. A. (2006) Errors in the estimation of the variance: implications for multiple-probability fluctuation analysis. J. Neurosci. Methods 153, 250–260.
Sargent, P. B., Saviane, C., Nielsen, T. A., DiGregorio, D. A., and Silver, R. A. (2005) Rapid vesicular release, quantal variability and spillover contribute to the precision and reliability of transmission at a glomerular synapse. J. Neurosci. 25, 8173–8187.
Saviane, C., and Silver, R. A. (2006) Fast vesicle reloading and a large pool sustain high bandwidth transmission at a central synapse. Nature 439, 983–987.
Wadiche, J. I., and Jahr, C. E. (2001) Multivesicular release at climbing fiber-Purkinje cell synapses. Neuron 32, 301–313.
Oertner, T. G., Sabatini, B. L., Nimchinsky, E. A., and Svoboda, K. (2002) Facilitation at single synapses probed with optical quantal analysis. Nat. Neurosci. 5, 657–664.
Christie, J. M., and Jahr, C. E. (2006) Multivesicular release at Schaffer collateral-CA1 hippocampal synapses. J. Neurosci. 26, 210–216.
Harrison, J., and Jahr, C. E. (2003) Receptor occupancy limits synaptic depression at climbing fiber synapses. J. Neurosci. 23, 377–383.
Silver, R. A., Lubke, J., Sakmann, B., and Feldmeyer, D. (2003) High-probability uniquantal transmission at excitatory synapses in barrel cortex. Science 302, 1981–1984.
Silver, R. A., Cull-Candy, S. G., and Takahashi, T. (1996) Non-NMDA glutamate receptor occupancy and open probability at a rat cerebellar synapse with single and multiple release sites. J. Physiol. 494, 231–250.
DiGregorio, D. A., Nusser, Z., and Silver, R. A. (2002) Spillover of glutamate onto synaptic AMPA receptors enhances fast transmission at a cerebellar synapse. Neuron 35, 521–533.
Foster, K. A., and Regehr, W. G. (2004) Variance-mean analysis in the presence of a rapid antagonist indicates vesicle depletion underlies depression at the climbing fiber synapse. Neuron 43, 119–131.
Clements, J. (2003) Variance-mean analysis: a simple and reliable approach for investigating synaptic transmission and modulation. J. Neurosci. Methods 130, 115–125.
Feldmeyer, D., Lubke, J., Silver, R. A., and Sakmann, B. (2002) Synaptic connections between layer 4 spiny neurone-layer 2/3 pyramidal cell pairs in juvenile rat barrel cortex: physiology and anatomy of interlaminar signalling within a cortical column. J. Physiol. 538, 803–822.
Nielsen, T. A., DiGregorio, D. A., and Silver, R. A. (2004) Modulation of glutamate mobility reveals the mechanism underlying slow-rising AMPAR EPSCs and the diffusion coefficient in the synaptic cleft. Neuron 42, 757–771.
Bekkers, J. M., and Stevens, C. F. (1996) Cable properties of cultured hippocampal neurons determined from sucrose-evoked miniature EPSCs. J. Neurophysiol. 75, 1250–1255.
Acknowledgements
Supported by The Wellcome Trust, the MRC, and the EC. RAS is in receipt of a Wellcome Trust Senior Fellowship.
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Saviane, C., Silver, R.A. (2007). Estimation of Quantal Parameters With Multiple-Probability Fluctuation Analysis. In: Molnar, P., Hickman, J.J. (eds) Patch-Clamp Methods and Protocols. Methods in Molecular Biology™, vol 403. Humana Press. https://doi.org/10.1007/978-1-59745-529-9_19
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DOI: https://doi.org/10.1007/978-1-59745-529-9_19
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