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Updated: Jun 27, 2026
07:27
In vivo Calcium Imaging of Mouse Geniculate Ganglion Neuron Responses to Taste Stimuli
Published on: February 11, 2021
The calcium-sensing receptor in taste tissue
Ana San Gabriel1, Hisayuki Uneyama, Takami Maekawa
1Institute of Life Sciences, Ajinomoto Co. Inc., Suzuki-cho 1-1, Kawasaki-ku, Kawasaki 210-8681, Japan.
Biochemical and Biophysical Research Communications
|December 6, 2008
Summary
The extracellular calcium-sensing receptor (CaSR) may play a role in how we taste calcium. Researchers found CaSR in mammalian taste buds, suggesting a new pathway for calcium taste perception.
Area of Science:
- Neuroscience
- Physiology
- Sensory Biology
Background:
- Calcium is vital, imparting a unique taste, yet its tongue-sensing mechanism remains unclear.
- Previous research linked calcium taste to the T1R3 receptor.
- The extracellular calcium-sensing receptor (CaSR) regulates calcium homeostasis via parathyroid and kidney functions.
Purpose of the Study:
- To investigate the potential role of the extracellular calcium-sensing receptor (CaSR) in calcium taste perception.
- To determine the presence and localization of CaSR within mammalian gustatory tissues.
Main Methods:
- Immunohistochemical analysis of CaSR expression in taste buds of rats and mice.
- Localization of CaSR within specific papillae types (circumvallate, foliate, fungiform).
Main Results:
- CaSR was detected in isolated taste buds from rat and mouse models.
- CaSR expression was observed in a subset of cells across different papillae, notably in circumvallate and foliate papillae.
- Fewer CaSR-expressing cells were found in fungiform papillae.
Conclusions:
- This study provides the first evidence of CaSR localization in mammalian gustatory tissue.
- The findings suggest CaSR as a potential key player in the sensing mechanism of calcium taste.
- This research opens new avenues for understanding the taste of calcium and other CaSR agonists.
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