Bioferroelectricity: Modeling the transitions of the sodium channel

A thermodynamic model for a phase transition in sodium channels between a ferroelectric “closed” phase and an ion-conducting “open” phase is discussed. This model implies Curie-Weiss behavior in the dielectric properties of excitable membranes, and this is consistent with data from squid axon. The question as to whether a ferroelectric phase as small as a macromolecule of 270 kD can exist is analyzed. A molecular interpretation of the transitions is given in terms of helix-coil transitions. “True relations may exist between ferroelectricity, the formation of liquid crystals, and the generation of electric impulses in nerves and muscles.”—A. R. von Hippel, 1970