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. 1966 Nov 1;50(2):243–253. doi: 10.1085/jgp.50.2.243

The Effects of External Sodium and Potassium Concentration on the Membrane Potential of Atrioventricular Fibers of the Toad

Tomio Kanno 1, Kojiro Matsuda 1
PMCID: PMC2225646  PMID: 11526826

Abstract

Intracellular records were made from fibers in the A-V conducting system of isolated toad hearts. The A-V region was perfused with Ringer's solution of various K and Na concentrations. Resting potential in 2.8 mM [K]o was about 60 mv. Over the range 0.28 to 28 mM, resting potential diminished with increasing [K]o. Spontaneous action potentials appeared when [K]o was increased to 11.2 mM, and when resting potential had fallen to about 40 to 50 mv. Changes in [Na]o over the range 22 to 110 mM had a little effect on resting potential, but there was a linear relation between the peak value of the action potential and log [Na]o Wenckebach periodicity was observed when [Na]o was lowered.

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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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