|
|
||||||||
Departments of 1 Physiology and
2 Medicine,
HCl- and NaCl-induced hamster chorda tympani nerve responses were recorded during voltage clamp of the lingual receptive field. Voltage perturbations did not influence responses to HCl. In contrast, responses to NaCl were decreased by submucosal-positive and increased by submucosal-negative voltage clamp. Responses to HCl were insensitive to the Na+ channel blockers, amiloride and benzamil, and to methylisobutylamiloride (MIA), an Na+/H+ exchange blocker. Responses to NaCl were unaffected by MIA but were suppressed by benzamil. Microfluorometric and imaging techniques were used to monitor the relationship between external pH (pHo) and the intracellular pH (pHi) of fungiform papilla taste receptor cells (TRCs) following 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein loading. TRC pHi responded rapidly and monotonically to changes in pHo. This response was unaffected by Na+ removal or the presence of amiloride, benzamil, or MIA. The neural records and the data from isolated TRCs suggest that the principal transduction pathway for acid taste in hamster is similar to that in rat. This may involve the monitoring of changes in TRC pHi mediated through amiloride-insensitive H+ transport across TRC membranes. This is an example of cell monitoring of environmental pH through pH tracking, i.e., a linear change in pHi in response to a change in pHo, as has been proposed for carotid bodies. In taste, the H+ transport sites may be concentrated on the basolateral membranes of TRCs and, therefore, are responsive to an attenuated H+ concentration from diffusion of acids across the tight junctions.
lingual voltage clamp; microfluorometry; imaging; fungiform papillae
This article has been cited by other articles:
![]() |
R. W. Putnam, J. A. Filosa, and N. A. Ritucci Cellular mechanisms involved in CO2 and acid signaling in chemosensitive neurons Am J Physiol Cell Physiol, December 1, 2004; 287(6): C1493 - C1526. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. K. Vinnikova, R. I. Alam, S. A. Malik, G. L. Ereso, G. M. Feldman, J. M. McCarty, M. A. Knepper, G. L. Heck, J. A. DeSimone, and V. Lyall Na+-H+ Exchange Activity in Taste Receptor Cells J Neurophysiol, March 1, 2004; 91(3): 1297 - 1313. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. P. McCluskey and D. L. Hill Sensitive periods for the effect of dietary sodium restriction on intact and denervated taste receptor cells Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2002; 283(5): R1275 - R1284. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Lin, T. Ogura, and S. C. Kinnamon Acid-Activated Cation Currents in Rat Vallate Taste Receptor Cells J Neurophysiol, July 1, 2002; 88(1): 133 - 141. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Lyall, R. I. Alam, T.-H. T. Phan, D. Q. Phan, G. L. Heck, and J. A. DeSimone Excitation and Adaptation in the Detection of Hydrogen Ions by Taste Receptor Cells: A Role for cAMP and Ca2+ J Neurophysiol, January 1, 2002; 87(1): 399 - 408. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Lyall, R. I. Alam, D. Q. Phan, G. L. Ereso, T.-H. T. Phan, S. A. Malik, M. H. Montrose, S. Chu, G. L. Heck, G. M. Feldman, et al. Decrease in rat taste receptor cell intracellular pH is the proximate stimulus in sour taste transduction Am J Physiol Cell Physiol, September 1, 2001; 281(3): C1005 - C1013. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. B. Katz, M. A. L. Nicolelis, and S. A. Simon Nutrient Tasting and Signaling Mechanisms in the Gut. IV. There is more to taste than meets the tongue Am J Physiol Gastrointest Liver Physiol, January 1, 2000; 278(1): G6 - G9. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. DeSimone Focus on "Rapid entry of bitter and sweet tastants into liposomes and taste cells: implications for signal transduction" Am J Physiol Cell Physiol, January 1, 2000; 278(1): C13 - C16. [Full Text] [PDF] |
||||
![]() |
V. Lyall, G. L. Heck, J. A. DeSimone, and G. M. Feldman Effects of osmolarity on taste receptor cell size and function Am J Physiol Cell Physiol, October 1, 1999; 277(4): C800 - C813. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |