Breadth of tuning in taste afferent neurons varies with stimulus strength.
Breadth of tuning in taste afferent neurons varies with stimulus strength.
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DOI：
10.1038/ncomms9171
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发表时间：
2015-09-16
影响因子：
16.6
通讯作者：
Roper SD
中科院分区：
文献类型：
--
作者：
Wu A;Dvoryanchikov G;Pereira E;Chaudhari N;Roper SD
味觉刺激由味蕾感知，并通过感觉传入神经元传递到后脑。每一种味道（甜的、苦的等等）是否由不同的神经元（“标记线”）编码仍然存在争议。我们使用在膝状神经节感觉神经元中表达GCaMP3的小鼠来研究味觉诱发活动。使用共聚焦钙成像，我们记录了对口腔刺激和原型味觉刺激的反应。高达69%的神经元对多种味觉剂有反应。此外，当刺激以更高的浓度呈现时，在低浓度下调谐到单一味觉质量的神经元会变得更广泛。对蔗糖和味精的反应最为相关。虽然小鼠更喜欢稀释的NaCl溶液，而不喜欢浓缩的NaCl溶液，但我们没有发现两种不同的感觉神经元群体编码这种区别的证据。总之，我们的数据表明，味觉是通过外周感觉神经元的活动模式进行编码的，这挑战了严格标记线编码的概念。味觉信息是如何被编码并从外围传递到皮层的，目前还不清楚。在这里，作者通过证明超过一半的单个膝状神经节神经元广泛地适应基本的味觉刺激，为基于群体的味觉编码提供了证据。
Gustatory stimuli are detected by taste buds and transmitted to the hindbrain via sensory afferent neurons. Whether each taste quality (sweet, bitter and so on) is encoded by separate neurons (‘labelled lines') remains controversial. We used mice expressing GCaMP3 in geniculate ganglion sensory neurons to investigate taste-evoked activity. Using confocal calcium imaging, we recorded responses to oral stimulation with prototypic taste stimuli. Up to 69% of neurons respond to multiple tastants. Moreover, neurons tuned to a single taste quality at low concentration become more broadly tuned when stimuli are presented at higher concentration. Responses to sucrose and monosodium glutamate are most related. Although mice prefer dilute NaCl solutions and avoid concentrated NaCl, we found no evidence for two separate populations of sensory neurons that encode this distinction. Altogether, our data suggest that taste is encoded by activity in patterns of peripheral sensory neurons and challenge the notion of strict labelled line coding. How taste information is encoded and transmitted from the periphery to the cortex is not well understood. Here the authors provide evidence for population-based coding of taste by demonstrating that more than half of individual geniculate ganglion neurons are broadly tuned to basic taste stimuli.