Reaction kinetic parameters for ion transport from steady-state current-voltage curves

Biophys J. 1987 Apr;51(4):569-85. doi: 10.1016/S0006-3495(87)83382-9.


This study demonstrates possible ways to estimate the rate constants of reaction kinetic models for ion transport from steady-state current-voltage data as measured at various substrate concentrations. This issue is treated theoretically by algebraic reduction and extension of a reaction kinetic four-state model for uniport. Furthermore, an example for application is given; current-voltage data from an open K+ selective channel (Schroeder, J.I., R. Hedrich, and J.M. Fernandez, 1984, Nature (Lond.), 312:361-362) supplemented by some new data have been evaluated. The analysis yields absolute numerical estimates of the 14 rate constants of a six-state model, which is discussed in a wider context.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electric Conductivity
  • Ion Channels / physiology*
  • Kinetics
  • Mathematics
  • Models, Biological*
  • Potassium / metabolism
  • Sodium / metabolism
  • Sodium-Potassium-Exchanging ATPase / metabolism


  • Ion Channels
  • Sodium
  • Sodium-Potassium-Exchanging ATPase
  • Potassium