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. 1981 Feb;33(2):281–288. doi: 10.1016/S0006-3495(81)84890-4

Membrane currents following activity in canine cardiac Purkinje fibers.

I Cohen, R Falk, R Kline
PMCID: PMC1327429  PMID: 7225509

Abstract

Recent experiments in canine Pukinje fibers (Gadsby and Cranefield, 1979) have shown that following a period of sodium loading in K+-free solution a slowly decaying outward current is observed. This current has been attributed to the activity of the electrogenic Na+-K+ exchange pump. In the present paper we show that similar slowly decaying outward currents are observed following prolonged periods of overdrive with action potentials or with brief depolarizing voltage clamp pulses. The dependent of the prolonged outward current on the duration and frequency of the preceding period of overdrive and on the potential following overdrive is reported. We also present results which indicate that a large portion of this current can be induced by phasic Na+ loading through the fast-inward channel.

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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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