Ninomiya Y, Tanimukai T, Yoshida S, Funakoshi M
Department of Oral Physiology, Asahi University School of Dentistry, Gifu Japan.
Physiol Behav. 1991 May;49(5):913-8. doi: 10.1016/0031-9384(91)90203-z.
Taste sensitivity of preweanling mice was studied by examining responses of the chorda tympani (CT) and glossopharyngeal (GL) nerves to various taste stimuli, and was compared to that of adult mice. In mice of 7-10 days of age, comparing to that of the CT nerve, threshold of the GL nerve for monosodium l-glutamate (MSG) was low, but those for sucrose and NaCl were high. Sensitivities to HCl and quinine-HCl were similar between the CT and GL nerves, although that to quinine-HCl was larger in the GL nerve than in the CT nerve in adult mice. Enhancement of MSG responses by addition of GMP was observed in the CT nerve but not in the GL nerve in this age group. In mice of 8-16 weeks of age, threshold of the GL nerve for MSG became higher but that for NaCl became lower. Enhancement of MSG responses by addition of GMP appeared also in the GL nerve. Inhibition of NaCl responses by amiloride was observed in the CT nerve. These results suggest that, in mice, the GL nerve is important taste input for umami substances especially during the preweanling period, whereas the CT nerve is for sweet and salty substances. Properties of umami and salt receptor systems change during the postweanling period.
通过检测鼓索神经（CT）和舌咽神经（GL）对各种味觉刺激的反应，研究了断奶前小鼠的味觉敏感性，并与成年小鼠进行了比较。在7 - 10日龄的小鼠中，与CT神经相比，GL神经对L - 谷氨酸钠（MSG）的阈值较低，但对蔗糖和氯化钠的阈值较高。CT神经和GL神经对盐酸和盐酸奎宁的敏感性相似，尽管在成年小鼠中，GL神经对盐酸奎宁的敏感性比CT神经更大。在这个年龄组中，CT神经中观察到添加鸟苷酸（GMP）可增强MSG反应，而GL神经中未观察到。在8 - 16周龄的小鼠中，GL神经对MSG的阈值升高，但对氯化钠的阈值降低。添加GMP对MSG反应的增强在GL神经中也出现了。在CT神经中观察到氨氯吡咪对氯化钠反应的抑制作用。这些结果表明，在小鼠中，GL神经是鲜味物质的重要味觉输入，尤其是在断奶前阶段，而CT神经是甜味和咸味物质的味觉输入。断奶后阶段，鲜味和盐受体系统的特性会发生变化。
