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. 1966 Sep;6(5):553–566. doi: 10.1016/S0006-3495(66)86677-8

Slow Changes of Potassium Permeability in the Squid Giant Axon

Gerald Ehrenstein, Daniel L Gilbert
PMCID: PMC1368014  PMID: 5970562

Abstract

A slow potassium inactivation i.e. decrease of conductance when the inside of the membrane is made more positive with respect to the outside, has been observed for the squid axon. The conductance-potential curve is sigmoid shaped, and the ratio between maximum and minimum potassium conductance is at least 3. The time constant for the change of potassium conductance with potential is independent of the concentration of potassium in the external solution, but dependent upon potential and temperature. At 9°C and at the normal sea water resting potential, the time constant is 11 sec. For lower temperature or more depolarizing potentials, the time constant is greater. The inactivation can be described by modifying the Hodgkin-Huxley equation for potassium current, using one additional parameter. The modified equation is similar in form to the Hodgkin-Huxley equation for sodium current, suggesting that the mechanism for the passive transport of potassium through the axon membrane is similar to that for sodium.

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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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