[Time dependence of the reaction rate constant of potassium permeability of Ranvier's node membrane].

To describe the kinetics of potassium permeability (conductance) changes in the squid giant axon membrane the Hodgkin--Huxley formulation uses a single first-order in time variable n with forward and backward rate constants, respectively alpha-n and beta-n, potential-dependent but time-independent. It has been shown by Frankenhaeuser that in the potassium-carrying system of the myelinated nerve fiber membrane of Xenopus laevis the rate constant beta-n is dependent on the duration of previous depolarization, i. e.