1998/11/05 by L. P. Endresen, Lars Petter Endresen, Kevin D. Hall +9
Biochemistry, Genetics and Molecular Biology · Medicine · Neuroscience · Physics and Astronomy · #Biological Physics (physics.bio-ph) #Cardiac electrophysiology and arrhythmias #Classical Physics (physics.class-ph) #FOS: Biological sciences #FOS: Physical sciences #Neuroscience and Neural Engineering #Quantitative Biology (q-bio) #physics.bio-ph #physics.class-ph #q-bio
paper · pdf · doi:10.48550/arxiv.physics/9811011
22 pages and 3 figures
arxiv created 1998/11/05 · openalex publication_date 1998/11/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We give an explicit formula for the membrane potential of cells in terms of the intracellular and extracellular ionic concentrations, and derive equations for the ionic currents that flow through channels, exchangers and electrogenic pumps. We demonstrate that the work done by the pumps equals the change in potential energy of the cell, plus the energy lost in downhill ionic fluxes through the channels and exchangers. The theory is illustrated in a simple model of spontaneously active cells in the cardiac pacemaker. The model predicts the experimentally observed intracellular ionic concentration of potassium, calcium, and sodium. Likewise the shapes of the simulated action potential and five membrane currents are in good agreement with experiments. We do not see any drift in the values of the concentrations in a long time simulation, and we obtain the same asymptotic values when starting from the full equilibrium situation with equal intracellular and extracellular ionic concentrations.