Nicholai Salovich with Daniel Scherson (Dept. of Chemistry)

Toward a Mesoscopic Description of Ion Channels and Nerve Conduction in Biological Membranes

Nerve impulses in the brain and muscle propagate through the depolarization of specific cellular membranes. Depolarization occurs when a stimulus of some sort triggers the opening of ion channels embedded in the membrane. The change in local potential due to the newly opened ion channel can then trigger the opening of yet more ion channels which in a cascading effect can cause a large propagating current pulse. Ion channels then spontaneously close and the membrane undergoes repolarization prior to another triggering.

Current models of this phenomenon approach the problem through an equivalent circuit representation and cable theory. This work will directly model current propagation through excitable tissue in a mesoscopic fashion. This approach differs from macroscopic and microscopic treatments because it regards ion channels as structureless but discrete elements that respond to differences in the local electrostatic potential, while also treating the membrane and the surrounding electrolyte as a continuous media.