Membrane permeability: cation selectivity reversibly altered by salicylate.

The effect of salicylate on the relative cation permeability of a membrane was investigated in large, identified molluscan neurons, with the use of intracellular recording techniques. Salicylate caused a reversible, dose-dependent decrease in the permeability of rubidium, cesium, sodium, and lithium ions relative to that of potassium ions. The results suggest that the changes in cation selectivity result from the adsorption of salicylate anions to the membrane with a subsequent increase in the density and field strength of anionic sites in the membrane.