Epithelial @entity4024 channel subunits in XXXX taste cells: localization and regulation by @entity1369 .

@entity1369 @entity4024 @entity1372 @entity6478 @entity1702 @entity1829 @entity35 @entity4202
@entity6478 -sensitive @entity4024 channels play an important role in transducing @entity4024 salt taste. Previous studies revealed that in rodent taste cells, the channel shares electrophysiological and pharmacological properties with the epithelial @entity4024 channel, ENaC. Using subunit-specific antibodies directed against alpha, beta, and gamma subunits of @entity35 ENaC (rENaC), we observed cytoplasmic immunoreactivity for all three subunits in nearly all taste cells of @entity1829 , and in about half of the taste cells in foliate and @entity1829 . The intensity of labeling in cells of @entity1829 was significantly lower than that of @entity1829 , especially for beta and gamma subunits. Dual localization experiments showed that immunoreactivity for the taste cell-specific G protein, gustducin, occurs in a subset ofrENaC positive taste cells. @entity1369 is known to increase the @entity6478 sensitivity of the @entity4202 taste response. In our study, increases in blood @entity1369 levels enhanced the intensity of apical immunoreactivity for beta and gamma rENaC in taste cells of all papillae. In addition, whole cell recordings from isolated taste cells showed that in @entity1829 , @entity1369 increased the number of @entity6478 -sensitive taste cells and enhanced the current amplitude. In vallate taste cells, which are normally unresponsive to @entity6478 , @entity1369 treatment induced an @entity6478 sensitive current in about half of the cells. Immunoreactivity for rENaC subunits also was present in nonsensory epithelial cells, especially in the anterior portion of the tongue. In addition, immunoreactivity for all subunits, but especially beta and gamma, was associated with some nerve fibers innervating @entity1702 . These extragustatory sites of rENaC expression may indicate a role for this channel in paracellular transduction of @entity1372 ions.
