Expression of ATP receptor P2X₃ subunit and taste signaling components in rat taste bud

Abstract

P2X₃ receptor in one of the ion channel receptors for ATP. This receptor is expressed in circumvallate, foliate and fungiform papillae but the functions of this receptor have not been revealed in taste buds. Alpha-gustducin and phospolipase Cβ2(PLCβ2) are the important signalling components in taste signalling system. In order to reveal the functions of P2X₃ in taste buds, we examined the localization of concentrated ATP and the relationships between P2X₃, α-gustducin and PLCβ2 using double-label immunohistochemistry method in rat circumvallate and fungiform papillae. P2X₃ positive nerve fibers connected to the α-gustducinor PLCβ2 positive cells in taste buds. These results suggest that ATP may play some roles in taste signaling system.