[Effect of 2,4 dinitrophenol and ouabain on the ability of cesium ions to substitute for intracellular potassium ions in isolated and perfused turtle heart (author's transl)].

1. It has been shown that most of the intracellular potassium of turtle heart can be replaced by cesium. 2. The uptake of cesium is reduced by the presence of either DNP 5.10(-5) M or ouabain 10(-6) M in the external medium. The presence of 10(-5) M ouabain markedly inhibits the uptake of cesium. 3. These results lead to the conclusion that the intracellular accumulation of cesium occurs via an active inward transport system wich operates with the simultaneous efflux of sodium.