Channel Noise

Part of the Springer Protocols Handbooks book series (SPH)


Patch-clamp is the best method for analyzing single-channel current activities today. The method is not good, however, at measuring the total number of channels expressed on the cell membrane that are responsible for the current of concern. In contrast, noise analysis has some advantage over the single-channel recording as a method to estimate the total number of ion channels. Also, noise analysis can obtain some channel information regarding size and kinetics even when individual channel events are so small to be detected directly as single-channel events. In this chapter the logic of noise analysis for stationary currents and nonstationary currents follows a description of several classic experiments conducted during the 1970s–1980s. Several technical issues frequently encountered during experiments are also addressed.


Corner Frequency Channel Noise Current Noise Noise Analysis Current Fluctuation 


  1. 1.
    Hagiwara S (1954) Analysis of interva1 fluctuation of the sensory nerve impulses. Jpn J Physiol 4:234–240PubMedCrossRefGoogle Scholar
  2. 2.
    Verveen AA, DeFelice LJ (1974) Membrane noise. Prog Biophys Mol Bio1 28:189–265CrossRefGoogle Scholar
  3. 3.
    Katz B, Miledi R (1970) Membrane noise produced by acetylcholine. Nature 226: 962–963PubMedCrossRefGoogle Scholar
  4. 4.
    Katz B, Miledi R (1970) Further observations on acetylcholine noise. Nature New Bio1 232:124–126Google Scholar
  5. 5.
    Stevens CF (1972) Inferences about membrane properties from electrical noise measurements. Biophys J 12:1028–1047PubMedCrossRefGoogle Scholar
  6. 6.
    Anderson CR, Stevens CF (1973) Voltage clamp analysis of acetylcholine produced end-plate current fluctuations at frog neuromuscular junction. J Physiol 235:655–691PubMedGoogle Scholar
  7. 7.
    Sigworth FJ (1977) Na channels in nerve apparently have two conductance states. Nature 270:265–267PubMedCrossRefGoogle Scholar
  8. 8.
    Sigworth FJ (1980) The variance of Na current fluctuations at the node of Ranvier. J Physio1 307:97–129Google Scholar
  9. 9.
    Verveen AA, Derksen HE (1965) Fluctuations in membrane potential of axons and problem of coding. Kybernetik 2:152–160Google Scholar
  10. 10.
    Poussart D (1971) Membrane current noise in lobster axon under voltage clamp. Biophys J 11:211–234PubMedCrossRefGoogle Scholar
  11. 11.
    Lee YW (1960) Statistical theory of communication. Wiley, New YorkGoogle Scholar
  12. 12.
    Bendat JS, Piersol AG (1971) Random data. Wiley-Interscience, New YorkGoogle Scholar
  13. 13.
    Ohmori H, Yoshida S, Hagiwara S (1981) Single K+ channel currents of anomalous rectification in cultured rat myotubes. Proc Natl Acad Sci USA 78:4960–4964PubMedCrossRefGoogle Scholar
  14. 14.
    Robinson HPC, Sahara Y, Kawai N (1991) Nonstationary fluctuation analysis and direct resolution of single channel currents at postsynaptic sites. Biophys J 59:295–304PubMedCrossRefGoogle Scholar
  15. 15.
    Traynelis SF, Jaramillo F (1998) Getting the most out of noise in the central nervous system. Trends Neurosci 21:137–145PubMedCrossRefGoogle Scholar
  16. 16.
    Brigham EO (1974) The fast Fourier transform. Prentice-Hall, Upper Saddle RiverGoogle Scholar
  17. 17.
    Hille B (1992) Ionic channels of excitable membranes. Sinauer Associates, SunderlandGoogle Scholar
  18. 18.
    Ohmori H (1981) Unitary current through sodium channel and anomalous rectifier channel estimated from transient current noise in the tunicate egg. J Physiol 311:289–305PubMedGoogle Scholar

Copyright information

© Springer 2012

Authors and Affiliations

  1. 1.Department of Physiology and Neurobiology, Faculty of MedicineKyoto UniversityKyotoJapan

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