A simple quantitative model of neuromodulation, Part II: Mechanosensitive channel gating

Abstract

We develop a simple model of mechanosensitive channel gating of neuronal ion channels as a function of applied strain. The model considers channel gating as a two-state system obeying transition-state theory with an elastic bias introduced by the applied strain. Compelled by observations of electric signaling in human neurons, which evince a lack of time-sigmoidicity of the channel conductances and an ability of the membrane voltage to jump instantaneously upon application of a step current, we propose a resistor model of membrane signaling that departs from conventional capacitor models such as Hodgkin–Huxley. We validate the theory on the basis of an in-house testing program of human-derived immortalized neural cell line at applied various strains, combining calcium imaging integrated tension bioreactors under fluorescence microscopes with high-speed cameras. The ability of the theory to reproduce the experimentally observed action potentials is remarkable.