Antagonism of veratrine by calcium ion in monolayers of stearic acid.

Force-area diagrams for monolayers of stearic acid on Ringer's solution demonstrate a competition between veratrine and calcium for carboxyl groups of the films. The competition occurs at customary concentrations. Local anesthetics act quite differently. The interactions suggest those observed less directly in living cells and therefore indicate that such surface films may serve as models for the study of drug and ion effects.