Effects of monovalent cations and some anions on the electrical properties of the barnacle muscle fiber membrane were studied when the intra- or extracellular concentrations of those ions were altered by longitudinal intra-cellular injection. The resting potential of the normal fiber decreases linearly with increase of logarithm of K(+)(out) and the decrement for a tenfold increase in K(+)(out) is 58 mv when the product, K(+)(out) .Cl(-)(out), is kept constant. It also decreases with decreasing K(+)(in) but is always less than expected theoretically. The deviation becomes larger as K(+)(in) increases and the resting potential finally starts to decrease with increasing K(+)(in) for K(+)(in) > 250 mM. When the internal K(+) concentration is decreased the overshoot of the spike potential increases and the time course of the spike potential becomes more prolonged. In substituting for the internal K(+), Na(+) and sucrose affect the resting and spike potentials similarly. Some organic cations (guanidine, choline, tris, and TMA) behave like sucrose while some other organic cations (TEA, TPA, and TBA) have a specific effect and prolong the spike potential if they are applied intracellularly or extracellularly. In all cases the active membrane potential increases linearly with the logarithm of Ca(++)(out)/K(+)(in) and the increment is about 29 mv for tenfold increase in this ratio. The fiber membrane is permeable to Cl(-) and other smaller anions (Br(-) and I(-)) but not to acetate(-) and larger anions (citrate(-), sulfate(-), and methanesulfonate(-)).
Hagiwara et al. (1964) studied this question.