H R Leuchtag

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In a 1969 experiment, Palti and Adelman reported that the capacitance of squid axon membrane rises sharply with temperature between 40 and 50 degrees C. This phenomenon is here explained by the ferroelectric-superionic transition hypothesis, which also explains channel gating and other phenomena observed in excitable membranes. According to this hypothesis(More)
Forces acting on the S4 segments of the channel, the voltage-sensing structures, are analyzed. The conformational change in the Na channel is modeled as a helix-coil transition in the four S4 segments, coupled to the membrane voltage by electrical forces. In the model, repulsions between like charges make the S4 segment unstable, but field-dependent forces(More)
Previous work in excitability has focused primarily on the mathematical description of the phenomena, while mechanisms postulated to explain these were simple mechanical interpretations of the terms of this description. The problem considered here is that of the physical mechanism underlying excitation. The experimental facts to be explained must be not(More)
The power spectrum of current fluctuations and the complex admittance of squid axon were determined in the frequency range 12.5 to 5,000 Hx during membrane voltage clamps to the same potentials in the same axon during internal perfusion with cesium. The complex admittance was determined rapidly and with high resolution by a fast Fourier transform(More)
Many investigators assert that the ion-conducting pathway of the Na channel is a water-filled pore. This assertion must be reevaluated to clear the way for more productive approaches to channel gating. The hypothesis of an aqueous pore leaves the questions of voltage-dependent gating and ion selectivity unexplained because a column of water can neither(More)
The hypothesis of ferroelectric electrodiffusion is examined mathematically. A thermodynamic potential, the elastic Gibbs function, written in polynomial form, provides the dielectric equation of state for the model. The other equations of electrodiffusion theory complete the model. This system reduces to a second-order partial differential equation, which(More)
This is the first of two papers dealing with electrodiffusion theory (the Nernst-Planck equation coupled with Gauss's law) and its application to the current-voltage behavior of squid axon. New developments in the exact analysis of the steady-state electrodiffusion problem presented here include (a) a scale transformation that connects a given solution to(More)
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