Alteration in nerve function following electroporation: A numerical modeling study of the electroporation conductance effect

Abstract

It is known that, after the application of sufficiently high external electric fields, defects are formed in the cell membrane at the molecular level, non-selectively increasing its permeability, and therefore increasing the conductance of the membrane to any ion. This phenomenon is called electroporation. Its effects may alter the excitable cell’s ability to depolarize. Experimentally, it has been observed that conduction velocity in nerve fibers and contraction force in muscles are lowered after the delivery of high electric fields. This bachelor’s thesis aims to develop a mechanistic model to assess whether it is plausible that those experimental observations are due to the direct effect of electroporation on the membrane. The cable model of an axon has been used to evaluate the effect of the increase of conductance due to electroporation on nerve fibers. The conductance increase has been modeled following two approaches at different level of detail: constant or dynamic. As hypothesized, the results suggest that the increase in membrane conductance due to electroporation may alter the function of nerve fibers, being able to reduce their conduction velocity, block completely the action potential propagation along them, and reduce their excitability. Moreover, in this bachelor’s thesis, it is also shown for the first time that the blocking effect of kilohertz frequency alternating currents may be related to electroporation of nerve fibers. In this way, the model would be useful to predict whether a nerve fiber would be temporally “deactivated”, given a certain distribution of the applied external voltage.