Cell-type specific expression of vanilloid receptor 1 in the taste cells of rat circumvallate papillae

Abstract

The present study demonstrates the first-ever characterization of cell types that express the vanilloid receptor 1 (VR1) in the taste buds of rat circumvallate papillae. We performed electron microscopy to identify the subcellular location. The VR1 immunoreactivity was associated with the endoplasmic reticulum, cytoplasmic vesicles, and plasma membrane of taste cells. These results demonstrate the localization of the VR1 in membranous structures of the taste cells. We used double immunofluorescence histochemistry with taste cell type-specific markers to identify the cell types that express the VR1. The VR1 was detected in all functional taste cell types (Type I, Type II, and Type III cells). Together, our data suggest that the VR1 might play different roles according to the cell types within a taste bud.