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. 1941 Jul 20;24(6):771–788. doi: 10.1085/jgp.24.6.771

LONGITUDINAL IMPEDANCE OF THE SQUID GIANT AXON

Kenneth S Cole 1, Richard F Baker 1
PMCID: PMC2238007  PMID: 19873252

Abstract

Longitudinal alternating current impedance measurements have been made on the squid giant axon over the frequency range from 30 cycles per second to 200 kc. per second. Large sea water electrodes were used and the inter-electrode length was immersed in oil. The impedance at high frequency was approximately as predicted theoretically on the basis of the poorly conducting dielectric characteristics of the membrane previously determined. For the large majority of the axons, the impedance reached a maximum at a low frequency and the reactance then vanished at a frequency between 150 and 300 cycles per second. Below this frequency, the reactance was inductive, reaching a maximum and then approaching zero as the frequency was decreased. The inductive reactance is a property of the axon and requires that it contain an inductive structure. The variation of the impedance with interpolar distance indicates that the inductance is in the membrane. The impedance characteristics of the membrane as calculated from the measured longitudinal impedance of the axon may be expressed by an equivalent membrane circuit containing inductance, capacity, and resistance. For a square centimeter of membrane the capacity of 1 µf with dielectric loss is shunted by the series combination of a resistance of 400 ohms and an inductance of one-fifth henry.

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Selected References

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

  1. Cole K. S. ELECTRIC PHASE ANGLE OF CELL MEMBRANES. J Gen Physiol. 1932 Jul 20;15(6):641–649. doi: 10.1085/jgp.15.6.641. [DOI] [PMC free article] [PubMed] [Google Scholar]
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