Sugar-induced transepithelial responses across the tongue epithelium of the frog Rana catesbeiana

Abstract Changes in transepithelial potential difference were induced across the dorsal tongue epithelium of frogs ( Rana catesbeiana ) by stimulation with various sugars. These were observed as a positive phase followed by a negative phase in the submucosa. The characteristics of the positive phase differed in many respects from those of the negative phase, and its profile resembled the activity of the gustatory nerve. The response was composed of a positive component superimposed on and masked by a negative component. In conclusion, the tissue absorbed sugar coupled with sodium and induced a positive component, and this may be related to gustatory transduction in frogs.