Salt and water transport by epithelial cells.
Epithelial cell volume is a sensitive indicator of the balance between solute entry into the cell and solute exit. Solute accumulation in the cell leads to cellular swelling because the water permeability of the cell membranes is high. Similarly, solute depletion leads to cellular shrinkage. The rate of volume change under a variety of experimental conditions may be utilized to study the rate and direction of solute transport by an epithelial cell. The pathways of water movement across an epithelium may also be deduced from the changes in cellular volume. A technique for the measurement of the volume of living epithelial cells is described and a number of experiments are discussed in which cellular volume determinations provided significant new information about the dynamic behavior of epithelia.
D000818:Animals; D001693:Biological Transport, Active; D002463:Cell Membrane Permeability; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005704:Gallbladder / Q000166:cytology; D009337:Necturus; D012965:Sodium Chloride / Q000378:metabolism*
D012965:Sodium Chloride