Goldmann equation

Also the Goldman-Hodgkin-Katz equation


 * Allows calculation of membrane potential based on intracellular and extracellular ion concentrations,
 * based on Nernst equation,
 * takes into account the real permeability of the resting membrane for ions.


 * $$E = \frac {RT}{F} \ln \frac { P_{Na^{+}}[Na_o^{+}] + P_{K^{+}}[K_o^{+}] + P_{Cl^{-}}[Cl_i^{-}] }{ P_{Na^{+}}[Na_i^{+}] + P_{K^{+}}[K_i^{+}] + P_{Cl^{-}}[Cl_o^{-}]},$$

where Px − relative permeability for the given ion.

The result is a resting membrane potential value of -73 mV, as opposed to the Nernst equation, where the result is -90 mV (Nernst equation does not take into account the real permeability of the membrane to ions).

Related Articles

 * Membrane Potential
 * Nernst equation
 * Inorganic components of the extracellular space