Effect of Chorda Tympani Nerve Transection on Salt Taste Perception in Mice

摘要

Effects of gustatory nerve transection on salt taste have been studied extensively in rats and hamsters but have not been well explored in the mouse. We examined the effects of chorda tympani (CT) nerve transection on NaCI taste preferences and thresholds in outbred CD-1 mice using a high-throughput phenotyping method developed in our laboratory. To measure taste thresholds, mice were conditioned by oral self-administration of LiCl or NaCI and then presented with NaCI concentration series in 2-bottle preference tests. LiCl-conditioned and control NaCI-exposed mice were given bilateral transections of the CT nerve (LiCl-CTX, NaCI-CTX) or were left intact as controls (LiCl-CNT, NaCI-CNT). After recovery from surgery, mice received a concentration series of NaCI (0-300 mM) in 48-h 2-bottle tests. CT transection increased NaCI taste thresholds in LiCl-conditioned mice and eliminated avoidance of concentrated NaCI in control NaCI-exposed mice. This demonstrates that in mice, the CT nerve is important for detection and recognition of NaCI taste and is necessary for the normal avoidance of high concentrations of NaCI. The results of this experiment also show that the method of high-throughput phenotyping of salt taste thresholds is suitable for detecting changes in the taste periphery in mouse genetic studies.