Fatty acid modulation of K+ channels in taste receptor cells: gustatory cues for dietary fat

Am J Physiol. 1997 Apr;272(4 Pt 1):C1203-10. doi: 10.1152/ajpcell.1997.272.4.C1203.


In an attempt to determine the chemosensory cues, if any, provided by fats in the oral cavity, we have performed patch-clamp recordings on isolated rat taste receptor cells during application of free fatty acids. Cis-polyunsaturated fatty acids, when applied extracellularly, inhibit delayed-rectifying K+ channels. In a subset of cells, these fatty acids also enhance inwardly rectifying K+ currents. Saturated, monounsaturated, and trans-polyunsaturated fatty acids have no significant effect on K+ currents. These effects do not involve activation of G protein-mediated pathways, including protein kinase C and protein kinase A, lipoxygenase pathways, cyclooxygenase pathways, or cytochrome P-450 pathways, consistent with direct effects on these ion channels or closely associated proteins. The net effect of fatty acids is to prolong stimulus-induced depolarizations of taste receptor cells, and we propose the effects on K+ channels represent the mechanism by which fats are detected by receptor cells in the oral cavity.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Arachidonic Acid / pharmacology
  • Cues
  • Dietary Fats / pharmacology*
  • Fatty Acids / pharmacology*
  • Male
  • Osmolar Concentration
  • Patch-Clamp Techniques
  • Potassium Channel Blockers*
  • Potassium Channels / drug effects
  • Potassium Channels / physiology
  • Rats
  • Rats, Sprague-Dawley
  • Sensory Receptor Cells / metabolism*
  • Taste / physiology*
  • Taste Buds / cytology
  • Taste Buds / drug effects
  • Taste Buds / metabolism*
  • Time Factors


  • Dietary Fats
  • Fatty Acids
  • Potassium Channel Blockers
  • Potassium Channels
  • Arachidonic Acid