Gustatory Responses of the Mouse Chorda Tympani Nerve Vary Based on Region of Tongue Stimulation
Gustatory Responses of the Mouse Chorda Tympani Nerve Vary Based on Region of Tongue Stimulation
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DOI：
10.1093/chemse/bjv015
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发表时间：
2015-06-01
期刊：
影响因子：
3.5
通讯作者：
McCaughey, Stuart A.
中科院分区：
文献类型：
--
作者：
Dana, Rachel M.;McCaughey, Stuart A.
口腔的不同部位的味觉反应能力和味觉传导成分各不相同。然而，很少有人尝试考虑由单个神经分支支配的区域或仅包含一种类型的味觉乳头的区域之间的区域差异。在这里，我们检查了单一神经鼓索（CT）的味觉反应是否取决于味觉溶液在小鼠舌头上的传递位置。在实验 1 中，如果将有味道的味觉溶液施加到包含最前面的菌状乳头的舌尖，则对 NaCl 和蔗糖的多单位 CT 响应比将它们流过后舌上的菌状乳头和叶状乳头时更大。此外，上皮钠通道 (ENaC) 阻滞剂阿米洛利更大程度地抑制舌尖的 NaCl 反应。在实验 2 中，比较了舌尖和仅包含菌状乳头的更靠后区域之间的 CT 神经反应。应用于后菌状乳头的氯化钠和蔗糖溶液产生的反应比应用于舌尖前菌状乳头的相同味觉刺激所引起的反应更小。阿米洛利抑制了递送至前蕈状乳头的 NaCl 反应，但不抑制后蕈状乳头的反应。这些结果表明 CT 响应在小鼠中依赖于舌头区域。此外，菌状乳头的空间位置提供了有关其特性的重要信息，例如钠味觉转导是否由阿米洛利敏感的 ENaC 介导。
Different parts of the mouth vary in their taste responsiveness and gustatory transduction components. However, there have been few attempts to consider regional variation among areas innervated by a single nerve branch or containing only one type of gustatory papilla. Here, we examined whether taste-elicited responses of a single nerve, the chorda tympani (CT), depend on where taste solutions are delivered on the tongue in mice. In experiment 1, multiunit CT responses to NaCl and sucrose were larger if sapid taste solutions were applied to the tongue tip, which contains the anterior-most fungiform papillae, than if they were flowed over fungiform and foliate papillae on the posterior tongue. Further, the epithelial sodium channel (ENaC) blocker amiloride suppressed NaCl responses to a greater degree for the tongue tip. In experiment 2, CT nerve responses were compared between the tongue tip and a region further back that contained only fungiform papillae. NaCl and sucrose solutions applied to posterior fungiform papillae produced smaller responses than did those elicited by the same taste stimuli applied to anterior fungiform papillae on the tongue tip. Amiloride suppressed the response to NaCl delivered to the anterior fungiform but not posterior fungiform papillae. These results indicate that the CT response is tongue-region dependent in the mouse. Furthermore, the spatial location of a fungiform papilla provides important information about its properties, such as whether sodium taste transduction is mediated by amiloride-sensitive ENaCs.