Volume expansion sensitivity of swelling-activated Cl(-) channel in human epithelial cells.

In human epithelial cell lines, whole-cell swelling-activated Cl(-) current was not directly correlated to cell volume per se, membrane tension or hydrostatic pressure. The current density exhibited a relation described by a Boltzmann function to the square of the cell diameter. Cytochalasin D enhanced the volume sensitivity. These results suggest that the activation mechanism of volume-sensitive Cl(-) channel is related to cytoskeleton-dependent membrane spring energy in human epithelial cells.