Current flow during PAP in squid axon at diameter change (Joyner et al 1980)

From the paper abstract: An impulse ... sees an increased electrical load at regions of increasing diameter or at branch points with certain morphologies. We present here theoretical and experimental studies on the changes in membrane current and axial current associated with diameter changes. The theoretical studies were done with numerical solutions for cable equations that were generalized to include a varying diameter; the Hodgkin-Huxley equations were used to represent the membrane properties. ... As an action potential approaches a region of increased electrical load, the action potential amplitude and rate of rise decrease, but there is a marked increase in the magnitude of the inward sodium current. ... (See paper for more details.)

Model Type: Axon

Currents: I Na,t; I K

Model Concept(s): Influence of Dendritic Geometry; Axonal Action Potentials

Simulation Environment: NEURON

Implementer(s): Hines, Michael [Michael.Hines at]


Joyner RW, Westerfield M, MOORE JW. (1980). Effects of cellular geometry on current flow during a propagated action potential. Biophys J 31 [PubMed]