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. 1980 Sep;31(3):325–331. doi: 10.1016/S0006-3495(80)85062-4

Increased charge displacement in the membrane of myelinated nerve at reduced extracellular pH.

B Neumcke, W Schwarz, R Stämpfli
PMCID: PMC1328793  PMID: 6973369

Abstract

Asymmetry currents were measured in nodes of myelinated nerve fibers from Rana esculenta at extracellular pH values of 5.2, 7.0, and 8.1 by averaging the currents during and after 1-ms depolarizing and hyperpolarizing voltage pulses. The charge displacement in the nodal membrane was obtained by numerical integration of the asymmetry currents. Lowering the pH from 7.0 to 5.2 significantly slows down the kinetics of the fast charge displacement during depolarization but hardly affects the kinetics after repolarization. The pH reduction increases the maximum charge displacement during depolarization by 46%. No differences between asymmetry currents were found between pH 7.0 and 8.1. It is concluded that protonation by extracellular H+ ions may increase the net charge or the transition range of mobile subunits in the nerve membrane.

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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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