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.

中文翻译：

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苦味受体拮抗剂对小鼠行为舔responses反应的影响。

苦味受体TAS2Rs检测口腔中的有害化合物。最近的异源表达研究报道，某些化合物可作为人TAS2R的拮抗剂。例如，氨基酸衍生物（例如γ-氨基丁酸（GABA）和Nα，Nα-双（羧甲基）-L-赖氨酸（BCML））会阻止人TAS2R4介导的对奎宁的反应。丙磺舒抑制了由人TAS2R38介导的对苯硫脲的响应。在这项研究中，我们调查了这些人类苦味受体拮抗剂对小鼠行为舔responses反应的影响，以阐明这些化合物是否也起苦味阻滞剂的作用。在短期（10 s）舔测试中，添加GABA或BCML不会影响对苦味化合物（奎宁-HCl，地那铵和苯硫脲）的浓度依赖性舔响应。丙磺舒减少了对地那铵和苯硫脲的厌恶舔反应，但对奎宁-HCl却没有。此外，丙磺舒抑制了味觉细胞对苯硫脲的反应。这些结果表明，人TAS2Rs的某些苦味拮抗药可以改善小鼠的苦味。