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. 1975 Feb;15(2 Pt 1):119–136. doi: 10.1016/s0006-3495(75)85796-1

Quantitative description of the sodium conductance of the giant axon of Myxicola in terms of a generalized second-order variable.

L Goldman
PMCID: PMC1334599  PMID: 1111631

Abstract

A variety of experimental observations in Myxicola and other preparations indicate that the sodium conductance, gNa, has properties quite different from those described by the m and h variables of Hodgkin and Huxley. A new quantitative description of the gNa is presented in which the gNa is assumed to be proportional to the fifth power of a generalized second-order variable, i.e., gNa = g'Na times v to the fifth, v = -Kav + K2U = K3, U = K4U + K5v + K6. This model is shown to be able to quantitatively simulate all of the experimentally observed behavior of the gNa. A view of the sodium gate consistent with these kinetics is to imagine it to be composed of five independent subunits, each of the type A eq. B eq. C eq. A where A represents the resting state, B the conducting state, and C the inactivated state. A model in which the subunit is of the type A eq. B eq. C could not simulate the experimental observations. It was concluded that two processes are sufficient to account for all of the behavior of the gNa.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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