Electrical properties of isolated demyelinated rat nerve fibres

Acta Physiol Scand. 1981 Oct;113(2):161-6. doi: 10.1111/j.1748-1716.1981.tb06877.x.


Isolated large rat nerve fibres with diphtheria toxin induced paranodal demyelination were investigated. These fibres had increased membrane time constant of the demyelinated nodal segment, related to a large increase in capacitance (5 to 50 times). The resting conductance was less increased (2 to 3 times), meaning that the internodal axolemma has considerably higher resting resistance than the nodal membrane. A large variation in action potential amplitude was found which was unrelated to the size of the nodal widening and the passive electrical properties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Animals
  • Demyelinating Diseases / chemically induced
  • Diphtheria Toxin
  • Membrane Potentials
  • Nerve Fibers, Myelinated / physiology*
  • Neural Conduction
  • Rats
  • Rats, Inbred Strains
  • Sciatic Nerve / drug effects


  • Diphtheria Toxin