The John B. Pierce Laboratory, Yale School of Medicine, Yale University, New Haven, CT, USA.
Department of Surgery (Otolaryngology), Yale School of Medicine, Yale University, New Haven, CT, USA.
Chem Senses. 2019 Jan 1;44(1):61-68. doi: 10.1093/chemse/bjy072.
This study investigated the effect of temperature on taste and chemesthetic sensations produced by the prototypical salty and sour stimuli NaCl and citric acid. Experiment 1 measured the perceived intensity of irritation (burning, stinging) and taste (saltiness, sourness) produced on the tongue tip by brief (3 s) exposures to suprathreshold concentrations of NaCl and citric acid at 3 different temperatures (12, 34, and 42 °C). No significant effects of temperature were found on the taste or sensory irritation of either stimulus. Experiment 2 investigated the potential effects of temperature on sensory irritation at peri-threshold concentrations and its sensitization over time. Measurements were again made on the tongue tip at the same 3 temperatures. Heating was found to enhance the perception of irritation at peri-threshold concentrations for both stimuli, whereas cooling suppressed sensitization of irritation for NaCl but not for citric acid. These results (i) confirm prior evidence that perception of suprathreshold salty and sour tastes are independent of temperature; (ii) demonstrate that heat has only weak effects on sensory irritation produced by brief exposures to NaCl and citric acid; and (iii) suggest that sensitization of the irritation produced by NaCl and citric acid occur via different peripheral mechanisms that have different thermal sensitivities. Overall, the results are consistent with involvement of the heat-sensitive channel TRPV1 in the sensory irritation of both stimuli together with one or more additional channels (e.g., acid-sensing channel, epithelial sodium channel, TRPA1) that are insensitive to heat and may possibly be sensitive to cooling.
本研究调查了温度对典型咸味和酸味刺激物 NaCl 和柠檬酸产生的味觉和化学感觉的影响。实验 1 测量了在 3 种不同温度（12、34 和 42°C）下，短暂（3 秒）暴露于阈上浓度的 NaCl 和柠檬酸时舌头上产生的刺激性（灼烧感、刺痛感）和味觉（咸味、酸味）的感知强度。温度对两种刺激物的味觉或感官刺激性均无显著影响。实验 2 研究了温度对阈下浓度刺激的感官刺激性及其随时间的敏化作用的潜在影响。在相同的 3 种温度下，再次在舌头上进行测量。结果发现，加热增强了对两种刺激物阈下浓度刺激的感知，而冷却抑制了 NaCl 刺激的敏感性，但对柠檬酸的敏感性没有影响。这些结果：（i）证实了先前的证据，即对阈上咸和酸味的感知不受温度影响；（ii）表明热对 NaCl 和柠檬酸的短暂暴露产生的感官刺激性仅有微弱影响；（iii）表明 NaCl 和柠檬酸产生的刺激性敏化作用通过不同的外周机制发生，这些机制对热的敏感性不同，可能对冷却敏感。总的来说，这些结果与热敏感通道 TRPV1 参与两种刺激物的感官刺激性一致，同时还涉及一种或多种对热不敏感、可能对冷却敏感的其他通道（如酸感应通道、上皮钠通道、TRPA1）。
