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. 1981 Dec;36(3):723–733. doi: 10.1016/S0006-3495(81)84761-3

Potassium ion currents in the crayfish giant axon. Dynamic characteristics.

S H Young, J W Moore
PMCID: PMC1327655  PMID: 6275922

Abstract

The kinetics of the voltage-sensitive potassium channel in crayfish axon have been examined. The conductance increase after a step depolarization from rest can be described by a first-order kinetic process raised to the third power. When conditioning voltage levels preceded the test pulse, the steady-state conductance was found to be independent of initial conditions. Depolarizing conditioning voltages in general allowed superposition of test voltage potassium currents by a shift along the time axis. Hyperpolarizing conditioning voltages produced a delay in onset of conductance during the test pulse and changed the kinetics so that superposition was not possible. The delay increased during the hyperpolarization with a first-order lag having a time constant in the range of 1.5-3 ms. Return to the resting level caused recovery from the delayed state to follow a single exponential decay with a time constant of 1.9-2.2 ms. The steady state delay vs. voltage curves were not saturated at potentials as negative as -180 mV.

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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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