AJP - Regulatory, Integrative and Comparative Physiology, Vol 255, Issue 1 117-R122, Copyright © 1988 by American Physiological Society
Spatial map of salts and saccharides on dog tongue
J. L. Garvin, R. Robb and S. A. Simon
Department of Physiology, Duke University Medical Center, Durham, North Carolina 27710.
Front and rear regions of dog tongue were tested for spatial heterogeneity
with respect to monovalent chloride salts (NaCl, KCl, and NH4Cl) and sweet
tastants (sucrose, D-glucose, and L-glucose) by placing them in Ussing
chambers where the open-circuit potential, Voc, and short-circuit current,
Isc, were measured. The responses of Voc and Isc to 0.5 M NaCl were greater
in the front of the tongue than in the rear, whereas the responses of Voc
and Isc to 0.5 M sucrose were greater in the rear of the tongue than in the
front. These results are similar to those of published neurophysiological
measurements from the chorda tympani nerve and thalamus. These data suggest
that the spatial heterogeneities seen in higher taste centers are present
in the isolated lingual epithelium where primary taste transduction events
occur.
