Chloride-dependent cation conductance activated during cellular shrinkage

Science  31 Jul 1992:
Vol. 257, Issue 5070, pp. 669-671
DOI: 10.1126/science.1379742


A chloride (Cl-)-dependent, nonselective cation conductance was activated during cellular shrinkage and inhibited during cellular swelling or by extracellular gadolinium. The shrinking-induced, nonselective cation conductance and the swelling-induced anion conductance appear to function in the regulation of cell volume in airway epithelia. The shrinking-induced cation conductance had an unusual dependence on Cl-: partial replacement of extracellular Cl- with aspartate reduced the magnitude of the shrinking-enhanced current without accompanying changes in the reversal potential. The Cl- dependence of the nonselective cation conductance could provide a mechanism that tightly regulates Cl- secretion and sodium reabsorption in cells under osmotic stress.