Comparative studies of volume restoration following cold-stress induced swelling in renal tissues--I. Effects of ouabain, K+ free medium, colchicine and cytochalasin B on rat and rabbit kidney cortex slices.

1. Cold-stress-induced swelling in rabbit and rat kidney cortex slices cannot be due to the sole inhibition of a Na+/K+ exchange system. In these tissues indeed, ouabain induces no swelling and an exchange of Na+ for K+ or a l/l basis. Inhibition of K+ extrusion at low temperature has also to be taken into consideration. 2. Volume restoration at 27 degrees C after cold-stress-induced swelling is inhibited by ouabain in rabbit slices, not in rat ones. The inhibition in rabbit slices is concomitant with an increase in Na+ at levels higher than equilibrium with the external medium. 3. Volume restoration does not seem to implicate colchicine or cytochalasin B sensitive processes.