title: Membrane potential of squid axons: effect of internal and external ion concentration.
abstract: Transmembrane resting potentials of squid axons were measured with variation of intracellular salt concentrations. It was found that the dependence of resting potential on the extracellular K-ion concentration was practically unaffected by the change of ionic strength in the intracellular phase, and the relationship of membrane potential and the logarithm of extracellular K-ion concentration was a straight line with a slope of about 50 mV/10-fold extracellular K-ion concentration. Also, the degree of change in resting potential due to the change of intracellular K-ion concentration was not affected appreciably by the extracellular solution with various K-ion concentrations, and the membrane potentials were insensitive over a wide range of intracellular K-ion concentrations. It was also indicated that the observed transmembrane potentials are not explained by a conventional membrane potential theory.
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D049832:Decapodiformes; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D011188:Potassium / Q000494:pharmacology*
chemical_list: D011188:Potassium