title: Mechanism of conduction block in amphibian myelinated axon induced by biphasic electrical current at ultra-high frequency.
abstract: The mechanism of axonal conduction block induced by ultra-high frequency (≥ 20 kHz) biphasic electrical current was investigated using a lumped circuit model of the amphibian myelinated axon based on Frankenhaeuser-Huxley (FH) equations. The ultra-high frequency stimulation produces constant activation of both sodium and potassium channels at the axonal node under the block electrode causing the axonal conduction block. This blocking mechanism is different from the mechanism when the stimulation frequency is between 4 kHz and 10 kHz, where only the potassium channel is constantly activated. The minimal stimulation intensity required to induce a conduction block increases as the stimulation frequency increases. The results from this simulation study are useful to guide future animal experiments to reveal the different mechanisms underlying nerve conduction block induced by high-frequency biphasic electrical current.
authors.affiliation: Department of Urology, University of Pittsburgh, 700 Kaufmann Building, Pittsburgh, PA 15213, USA. cftai@pitt.edu
authors.forename: Changfeng
authors.initials: C
authors.lastname: Tai
authors.forename: Dong
authors.initials: D
authors.lastname: Guo
authors.forename: Jicheng
authors.initials: J
authors.lastname: Wang
authors.forename: James R
authors.initials: JR
authors.lastname: Roppolo
authors.forename: William C
authors.initials: WC
authors.lastname: de Groat
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001369:Axons / Q000502:physiology*; D004558:Electric Stimulation / Q000379:methods*; D004560:Electricity; D004594:Electrophysiology / Q000379:methods; D008959:Models, Neurological; D009413:Nerve Fibers, Myelinated / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D015221:Potassium Channels / Q000502:physiology; D011901:Ranvier's Nodes / Q000502:physiology; D015222:Sodium Channels / Q000502:physiology; D014982:Xenopus laevis / Q000502:physiology
chemical_list: D015221:Potassium Channels; D015222:Sodium Channels