A Discontinuous Model for Membrane Activity

  • Henrik Østergaard Madsen
  • Morten Colding-Jørgensen
  • Brian Bodholdt
Part of the NATO ASI Series book series (NSSB, volume 270)


A model for the excitable membrane is described. The model exhibits many types of firing patterns seen in excitable cells. The model includes potassium, sodium and calcium ions. These are affected by an active calcium pump, by potential dependent calcium, sodium and potassium conductances, and a calcium dependent potassium conductance. The cytosolic calcium concentration is buffered. Inactivation or time-delays of the conductances are not included, and the membrane capacity is zero. This leads to a discontinuous model, which is nevertheless capable of showing stable behavior, slow or fast spontaneous oscillations or bursting. To illustrate the generality of the model, it is adopted to mimic two specific cell types: a pancreatic β-cell and a cerebellar Purkinje cell.


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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • Henrik Østergaard Madsen
    • 1
  • Morten Colding-Jørgensen
    • 2
  • Brian Bodholdt
    • 1
  1. 1.Physics Laboratory IIIThe Technical University of DenmarkLyngbyDenmark
  2. 2.Department of General Physiology and BiophysicsThe Panum InstituteCopenhagen NDenmark

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