Network thermodynamic model of rat lingual epithelium: effects of hyperosmotic NaCl.
A network thermodynamic model was developed to describe steady-state and transient ion flows (Na+, K+, and Cl-) and related electrical events in the rat lingual epithelium. The model, which uses only standard assumptions about topology and membrane ion transport processes from other tight epithelia, successfully simulates steady-state transepithelial electrical measurements seen in the in vitro rat dorsal lingual epithelium for a wide range (50-2,000 mM) of mucosal NaCl concentrations. It also simulates the intracellular depolarization and subsequent repolarization observed in situ in rat taste cells in response to a mucosal hyperosmotic NaCl stimulus. Because the intracellular potential has been identified with the receptor potential for gustation, the depolarization and repolarization may explain both the phasic and tonic components of taste nerve excitation in response to a salt stimulus. This study suggests that a better understanding of taste transduction may be gained by focusing more attention on the transport properties and mechanisms of lingual epithelia.
Department of Physiology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298.
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ML
Fidelman
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Mierson
D000818:Animals; D001692:Biological Transport; D003198:Computer Simulation; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D008962:Models, Theoretical; D009092:Mucous Membrane / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D009994:Osmolar Concentration; D051381:Rats; D012965:Sodium Chloride / Q000494:pharmacology*; D013816:Thermodynamics; D014059:Tongue / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism
D012965:Sodium Chloride