Epithelial cell volume regulation: bicarbonate dependence.
When Necturus gallbladder epithelial cells are osmotically shrunken, they rapidly return to their original volume despite the continued presence of a hypertonic bathing solution. This volume-regulatory process requires bicarbonate ions in the bathing solutions and is associated with the uptake of chloride ions. Volume-regulatory increase by epithelial cells in probable due to the parallel operation of sodium-hydrogen and chloride-bicarbonate exchangers in the apical cell membrane.
D000818:Animals; D001639:Bicarbonates / Q000494:pharmacology*; D002463:Cell Membrane Permeability; D002712:Chlorides / Q000502:physiology; D004848:Epithelium / Q000502:physiology; D005704:Gallbladder / Q000502:physiology*; D008564:Membrane Potentials; D009337:Necturus; D012964:Sodium / Q000502:physiology; D014882:Water-Electrolyte Balance / Q000187:drug effects*
D001639:Bicarbonates; D002712:Chlorides; D012964:Sodium