Masamoto, Michimasa Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University
Mitoh, Yoshihiro Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kaken ID researchmap
Kobashi, Motoi Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kaken ID researchmap
Shigemura, Noriatsu Section of Oral Neuroscience, Graduate School of Dental Sciences, Kyushu University
Bitter taste receptors TAS2Rs detect noxious compounds in the oral cavity. Recent heterologous expression studies reported that some compounds function as antagonists for human TAS2Rs. For examples, amino acid derivatives such as γ-aminobutyric acid (GABA) and Nα,Nα-bis(carboxymethyl)-L-Lysine (BCML) blocked responses to quinine mediated by human TAS2R4. Probenecid inhibited responses to phenylthiocarbamide mediated by human TAS2R38. In this study, we investigated the effects of these human bitter receptor antagonists on behavioral lick responses of mice to elucidate whether these compounds also function as bitter taste blockers. In short-term (10 s) lick tests, concentration-dependent lick responses to bitter compounds (quinine-HCl, denatonium and phenylthiourea) were not affected by the addition of GABA or BCML. Probenecid reduced aversive lick responses to denatonium and phenylthiourea but not to quinine-HCl. In addition, taste cell responses to phenylthiourea were inhibited by probenecid. These results suggest some bitter antagonists of human TAS2Rs can work for bitter sense of mouse.
Masamoto M, Mitoh Y, Kobashi M, Shigemura N, Yoshida R. Effects of bitter receptor antagonists on behavioral lick responses of mice [published online ahead of print, 2020 May 12]. Neurosci Lett. 2020;135041. doi:10.1016/j.neulet.2020.135041