Submitted on March 11, 2005
Accepted on May 20, 2005
Expression and characterization of delayed rectifying K+ channels in anterior rat taste buds
Lidong Liu1, Dane R Hansen2, Insook Kim3, and Timothy A Gilbertson2*
1 Brain Research Centre, University of British Columbia, Vancouver, BC, Canada
2 Department of Biology & The Center for Integrated BioSystems, Utah State University, Logan, UT, USA
3 Department of Pediatrics, University of Arkansas Medical Sciences, Little Rock, AR, USA
* To whom correspondence should be addressed. E-mail: tag{at}biology.usu.edu.
Delayed rectifying potassium (DRK) channels in taste cells have been implicated in the regulation of cell excitability and as potential targets for direct and indirect modulation by taste stimuli. In the present study we have used patch clamp recording to determine the biophysical properties and pharmacological sensitivity of DRK channels in isolated rat fungiform taste buds. Molecular biological assays at the taste bud and single cell level are consistent with the interpretation that taste cells express a variety of DRK channels including members from each of the three major subfamilies, KCNA, KCNB and KCNC. Real-time PCR assays were used to quantify expression of the nine DRK channel subtypes. While taste cells express a number of DRK channels, the electrophysiological and molecular biological assays indicate that the Shaker Kv1.5 channel (KCNA5) is the major functional DRK channel expressed in the anterior rat tongue.
