Biophysical Journal 11: 1068-1084 (1971)
© 1971 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Lecar, H. Articles by Nossal, R. Search for Related Content PubMed PubMed Citation Articles by Lecar, H. Articles by Nossal, R.

Theory of Threshold Fluctuations in Nerves

II. Analysis of Various Sources of Membrane Noise

ABSTRACT

Threshold fluctuations in axon firing can arise as a result of electrical noise in the excitable membrane. A general theoretical expression for the fluctuations is applied to the analysis of three sources of membrane noise: Johnson noise, excess 1/f noise, and sodium conductance fluctuations. Analytical expressions for the width of the firing probability curve are derived for each of these noise sources. Specific calculations are performed for the node of Ranvier of the frog, and attention is given to the manner in which threshold fluctuations are affected by variations of temperature, ion concentrations, and the application of various drugs. Comparison with existing data suggests that threshold fluctuations can best be explained by sodium conductance fluctuations. Additional experiments directed at distinguishing among the various noise sources are proposed.

This article has been cited by other articles:

				N Moran, G Ehrenstein, K Iwasa, C Bare, and C Mischke Ion channels in plasmalemma of wheat protoplasts Science, November 16, 1984; 226(4676): 835 - 838. [Abstract] [PDF]