Neural Taste an Thermal Coding in Geniculate Ganglion

味觉是一种关键的感觉系统，用于对丰富的 潜在的食品在环境中被归入有益的营养类别 摄入，不需要的物品，以及要避免的毒素。有一个广泛的 来自各种物种的研究文献，专注于获得 理解品味是如何完成这一惊人壮举的 生物体的健康和福利。有越来越多的证据 这表明，味觉系统可能可以分为少数几个 子模式(例如，碳水化合物的甜味等)，尽管确切的数字 等待进一步调查。此外，一套独特的受体机制 以及负责将信息传递给 大脑可能服务于每个子通道。我们的总体目标是利用细胞外 单细胞记录技术，用于定义 味觉系统及其受体和神经反应的特征 属性。我们最近开发了一种新的长期稳定的制剂 记录味觉神经元的反应。我们建议的录音研究将是 来自面神经的膝状神经节。在神经节内有 神经细胞的单极胞体，支配大脑的味觉受体。 舌头和味觉。我们建议对化学和热学性质进行表征。 大鼠膝状神经节对舌、腭部刺激的敏感性 并检测特定的药理拮抗剂对味觉的影响 转导机制。将对老鼠进行研究是因为 神经和行为研究很大程度上来自老鼠，它是一种优秀的 人类摄取的模型，我们对这个物种有丰富的经验。 这项提案的具体目标是：(1)描述以下方面的反应 盐敏感和甜敏神经元对广泛的刺激 几种刺激浓度；(2)考察特定刺激浓度的影响 盐和甜味转导机制的药理拮抗剂； 描述不同神经元组对热刺激的反应 以评估味觉与热的相互作用；以及(4)确定脂肪和 蛋白质可以包括在传统上仅限于甜味的原味中， 咸的、酸的和苦的

Taste is a critical sensory system for sorting the rich array of potential foods in the environment into beneficial nutrient categories to be ingested, items not needed, and toxins to be avoided. There is an extensive research literature from a variety of species focused on gaining an understanding on how taste is capable of accomplishing this amazing feat for the health and welfare of the organism. There is a growing body of evidence that suggests that the gustatory system may be divisible into a small number of sub-modalities (e.g., sweet for carbohydrate, etc.), although the exact number awaits additional investigation. Further, a unique set of receptor mechanisms and group of neurons that are responsible for transmitting the information to the brain may serve each sub-modality. Our overall goal is to use extracellular single-cell recording techniques to define the number of sub modalities in the gustatory system and characterize their receptor and neural response properties. We have recently developed a new preparation for stable long-term recording of taste neuron responses. Our proposed recording studies will be from the geniculate ganglion of the facial nerve. Within the ganglion are the unipolar cell bodies of neurons that innervate the taste receptors on the tongue and palate. We propose to characterize the chemical and thermal sensitivity of the rat geniculate ganglion to lingual and palatal stimulation, and to examine the effects of specific pharmacological antagonists on taste transduction mechanisms. The rat will be studied because the vast background of neural and behavioral research comes largely from rats, it is an excellent model of human ingestion, and we have extensive experience with this species. The specific aims of this proposal are: (1) to characterize the responses of salt-sensitive and sweetsensitive neurons to a broad array of stimuli across several stimulus concentrations; (2) to examine the effects of specific pharmacological antagonists on salt and sweet transduction mechanisms; (3) to characterize the responses of various neuron groups to thermal stimulation and to assess taste-thermal interaction; and (4) to determine whether fat and protein can be included into primary taste traditionally restricted to sweet, salt, sour, and bitter.