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Gating Kinetics in Ionic Channels

  • L. Goldman
  • J. L. Kenyon

Abstract

It is now well established that the rising phase of the action potential seen in many nerve, muscle and cardiac cells generates from a selective increase in the membrane permeability to Na ions, PNa· When studied under voltage clamp, the changes in PNa which underlie the upstroke of the action potential are measured as changes in the electrical conductance, gNa· For a positive step change in the clamped membrane potential gNa is seen to, with a delay, rise to a peak value (activate) and then, even though the potential is held constant, to decline to a small value (inactivate). A central issue in the problem of the molecular organization of this Na channel gating machinery is the nature of the relation between the activation and inactivation processes.

Keywords

Voltage Clamp Test Pulse Tail Current Inactivation Curve Inactivation Time 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1985

Authors and Affiliations

  • L. Goldman
    • 1
  • J. L. Kenyon
    • 1
  1. 1.Department of Physiology School of MedicineUniversity of Maryland BaltimoreMarylandUSA

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