Sato T, Sugimoto K
Department of Physiology, Nagasaki University School of Dentistry, Japan.
Zoolog Sci. 1995 Feb;12(1):45-52. doi: 10.2108/zsj.12.45.
After frog taste cells were adapted to 1 mM quinine-HCl (Q-HCl) for 10 sec, modification of receptor potentials in the taste cells induced by salt, acid, sugar and bitter stimuli was studied with microelectrodes. The phasic component of receptor potentials induced by 0.1 M NaCl, KCl, NH4Cl and MgCl2 was enhanced following adaptation to Q-HCl. The rate of rise of receptor potentials in response to the salts was increased after Q-HCl adaptation. The amplitude and the rate of rise of receptor potentials induced by 1 mM acetic acid were larger after Q-HCl adaptation than after water adaptation. The amplitude of phasic component and rate of rise of receptor potentials for 0.5 M sucrose after Q-HCl were the same as those after water. The amplitudes of tonic receptor potentials for 1 mM Q-H2SO4, brucine and picric acid after Q-HCl adaptation were the same as those after 1 mM NaCl adaptation. Correlation coefficient between taste cell responses induced by 1 mM Q-HCl and 1 mM Q-H2SO4 was very high, but those between 1 mM Q-HCl and 1 mM brucine responses and between 1 mM Q-HCl and 1 mM picric acid responses were low. This indicates that Q-HCl and Q-H2SO4 bind to the same receptor site, but brucine and picric acid bind to different receptor sites to which Q-HCl does not bind.
将蛙的味觉细胞用1 mM盐酸奎宁（Q-HCl）适应10秒后，用微电极研究了盐、酸、糖和苦味刺激在味觉细胞中引起的感受器电位的变化。适应Q-HCl后，由0.1 M NaCl、KCl、NH4Cl和MgCl2诱导的感受器电位的相位成分增强。Q-HCl适应后，对盐类刺激产生反应时感受器电位的上升速率增加。适应Q-HCl后，1 mM乙酸诱导的感受器电位的幅度和上升速率比用水适应后更大。Q-HCl适应后，0.5 M蔗糖的感受器电位的相位成分幅度和上升速率与用水适应后相同。Q-HCl适应后，1 mM硫酸奎宁、马钱子碱和苦味酸的紧张性感受器电位幅度与1 mM NaCl适应后相同。1 mM Q-HCl和1 mM硫酸奎宁诱导的味觉细胞反应之间的相关系数非常高，但1 mM Q-HCl和1 mM马钱子碱反应之间以及1 mM Q-HCl和1 mM苦味酸反应之间的相关系数较低。这表明Q-HCl和硫酸奎宁结合到相同的受体位点，但马钱子碱和苦味酸结合到Q-HCl不结合的不同受体位点。
