Amiloride-blockable Sodium Currents in Isolated Taste Receptor Cells

Overview

Journal J Membr Biol

Date 1988 Nov 1

PMID 2851656

Citations 27

Authors

P Avenet

B Lindemann

Affiliations

Soon will be listed here.

Abstract

Isolated taste receptor cells from the frog tongue were investigated under whole-cell patch-clamp conditions. With the cytosolic potential held at -80 mV, more than 50% of the cells had a stationary inward Na current of 10 to 700 pA in Ringer's solution. This current was in some cells partially, in others completely, blockable by low concentrations of amiloride. With 110 mM Na in the external and 10 mM Na in the internal solution, the inhibition constant of amiloride was (at -80 mV) near 0.3 microM. In some cells the amiloride-sensitive conductance was Na specific; in others it passed both Na and K. The Na/K selectivity (estimated from reversal potentials) varied between 1 and 100. The blockability by small concentrations of amiloride resembled that of channels found in some Na-absorbing epithelia, but the channels of taste cells showed a surprisingly large range of ionic specificities. Receptor cells, which in situ express these channels in their apical membrane, may be competent to detect the taste quality "salty." The same cells also express TTX-blockable voltage-gated Na channels.

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References

Hamill O, Marty A, Neher E, Sakmann B, Sigworth F . Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981; 391(2):85-100. DOI: 10.1007/BF00656997. View

Akaike N, Noma A, Sato M . Electrical responses to frog taste cells to chemical stimuli. J Physiol. 1976; 254(1):87-107. PMC: 1309182. DOI: 10.1113/jphysiol.1976.sp011223. View

Brand J, Teeter J, Silver W . Inhibition by amiloride of chorda tympani responses evoked by monovalent salts. Brain Res. 1985; 334(2):207-14. DOI: 10.1016/0006-8993(85)90212-4. View

Tang C, Presser F, Morad M . Amiloride selectively blocks the low threshold (T) calcium channel. Science. 1988; 240(4849):213-5. DOI: 10.1126/science.2451291. View

Kinnamon S, Roper S . Membrane properties of isolated mudpuppy taste cells. J Gen Physiol. 1988; 91(3):351-71. PMC: 2216137. DOI: 10.1085/jgp.91.3.351. View

Warncke J, Lindemann B . Voltage dependence of the blocking rate constants of amiloride at apical Na channels. Pflugers Arch. 1985; 405 Suppl 1:S89-94. DOI: 10.1007/BF00581786. View

Benos D . The amiloride-sensitive sodium channel. Am J Physiol. 1986; 250(2 Pt 1):C175-90. DOI: 10.1152/ajpcell.1986.250.2.C175. View

Hill D, Bour T . Addition of functional amiloride-sensitive components to the receptor membrane: a possible mechanism for altered taste responses during development. Brain Res. 1985; 352(2):310-3. DOI: 10.1016/0165-3806(85)90121-x. View

Avenet P, Lindemann B . Patch-clamp study of isolated taste receptor cells of the frog. J Membr Biol. 1987; 97(3):223-40. DOI: 10.1007/BF01869225. View

10.

Palmer L, FRINDT G . Amiloride-sensitive Na channels from the apical membrane of the rat cortical collecting tubule. Proc Natl Acad Sci U S A. 1986; 83(8):2767-70. PMC: 323382. DOI: 10.1073/pnas.83.8.2767. View

11.

Palmer L . Ion selectivity of the apical membrane Na channel in the toad urinary bladder. J Membr Biol. 1982; 67(2):91-8. DOI: 10.1007/BF01868651. View

12.

Palmer L . Voltage-dependent block by amiloride and other monovalent cations of apical Na channels in the toad urinary bladder. J Membr Biol. 1984; 80(2):153-65. DOI: 10.1007/BF01868771. View

13.

Simon S, Robb R, Garvin J . Epithelial responses of rabbit tongues and their involvement in taste transduction. Am J Physiol. 1986; 251(3 Pt 2):R598-608. DOI: 10.1152/ajpregu.1986.251.3.R598. View

14.

Okada Y, Miyamoto T, Sato T . Arterial perfusion of frog tongue for intracellular recording of taste cell receptor potential. Comp Biochem Physiol A Comp Physiol. 1985; 81(2):247-50. DOI: 10.1016/0300-9629(85)90129-x. View

15.

Dragsten P, Blumenthal R, Handler J . Membrane asymmetry in epithelia: is the tight junction a barrier to diffusion in the plasma membrane?. Nature. 1981; 294(5843):718-22. DOI: 10.1038/294718a0. View

16.

Nakamura T, Gold G . A cyclic nucleotide-gated conductance in olfactory receptor cilia. Nature. 1987; 325(6103):442-4. DOI: 10.1038/325442a0. View

17.

Garty H, Benos D . Characteristics and regulatory mechanisms of the amiloride-blockable Na+ channel. Physiol Rev. 1988; 68(2):309-73. DOI: 10.1152/physrev.1988.68.2.309. View

18.

Tonosaki K, Funakoshi M . Voltage- and current-clamp recordings of the receptor potential in mouse taste cell. Brain Res. 1988; 445(2):363-6. DOI: 10.1016/0006-8993(88)91200-0. View

19.

Wills N, Zweifach A . Recent advances in the characterization of epithelial ionic channels. Biochim Biophys Acta. 1987; 906(1):1-31. DOI: 10.1016/0304-4157(87)90003-7. View

20.

Heck G, Mierson S, DeSimone J . Salt taste transduction occurs through an amiloride-sensitive sodium transport pathway. Science. 1984; 223(4634):403-5. DOI: 10.1126/science.6691151. View