[Demonstration of intracellular release of calcium induced by sodium ions in the auricular trabeculae of the frog].

Abstract

In a Ca-free, Mg-free medium containing EGTA (10-3M) auricular trabecles develop a slow inward current which is a pure sodium current. After 12 min in this medium, it is still possible to obtain a phasic mechanical activity which shows a perfect correlation with the current. This kind of behavior indicates that a mechanism of sodium-induced calcium release is present at the level of some internal sites.