Abstract: | Ehrlich ascites tumour cells are able, under the proper experimental conditions, to extrude a substantial amount of Ca2+ from the intracellular space. The Ca2+ extrusion mechanism, probably located at the plasma membrane level, appears to be similar to that found in red blood cells. It is energy-dependent and both respiration and glycolysis are able to drive it. The use of some inhibitors and uncouplers, besides showing that this activity is different from that linked to the mitochondrial Ca2+ pump which acts in the opposite direction, proposes some speculations on the energy compartmentation in the Ehrlich ascites tumour cells. |