Related Experiment Video
Updated: Mar 1, 2026

Whole-Mount Staining, Visualization, and Analysis of Fungiform, Circumvallate, and Palate Taste Buds
Published on: February 11, 2021
The cellular mechanism for water detection in the mammalian taste system
Dhruv Zocchi1, Gunther Wennemuth2, Yuki Oka1
1Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.
Abstract:
Initiation of drinking behavior relies on both internal state and peripheral water detection. While central neural circuits regulating thirst have been well studied, it is still unclear how mammals recognize external water. Here we show that acid-sensing taste receptor cells (TRCs) that were previously suggested as the sour taste sensors also mediate taste responses to water. Genetic silencing of these TRCs abolished water-evoked responses in taste nerves. Optogenetic self-stimulation of acid-sensing TRCs in thirsty animals induced robust drinking responses toward light even without water. This behavior was only observed when animals were water-deprived but not under food- or salt-depleted conditions, indicating that the hedonic value of water-evoked responses is highly internal-state dependent. Conversely, thirsty animals lacking functional acid-sensing TRCs showed compromised discrimination between water and nonaqueous fluids. Taken together, this study revealed a function of mammalian acid-sensing TRCs that provide a cue for external water.
Related Concept Videos
The Physiology of Taste
Gustation
Taste Buds and Receptors
G-Protein Gated Ion Channels
Sensory...
Regulation of Water Intake
Reabsorption and Secretion in the DCT and Collecting Duct
The distal...

