PLASTICITY OF THE REGENERATING TASTE SYSTEM

描述：(改编自申请人的摘要)对品味的依赖 支配它们的神经纤维上的芽被用作 了解神经/目标的相互作用。失去神经支配会导致损失 味蕾的正常形态外观，而恢复 神经支配导致味蕾形态和功能的恢复。 因此，退化再生的外周味觉系统 非常适合研究造血祖细胞的动态生物过程 最终形成成熟的、能够传递味觉的功能细胞 信息。首席调查员以前在实验室的工作 表明成人的味觉再生系统尤其是 容易受到环境操纵的影响。组合单侧脊索 成年大鼠鼓室神经切断术和低钠饮食对大鼠的影响 味蕾和味蕾的功能和解剖变化 再生神经。此外，影响并不局限于 舌侧切开，因为深奥的功能和解剖学 改变也发生在完整的对侧。要扩展这些功能 单个膝状神经节的神经生理味觉反应 在处理舌侧电压的过程中，细胞将被记录 对照组大鼠和饲喂全氯化钠或氯化钠的大鼠体内的上皮细胞 单侧鼓索神经切断后缺盐饮食的研究 在成年时。协调的形态研究将检查各种 参与受体细胞维持和再生的过程和 相关的神经元素。最后，神经活动的作用和 将探索免疫系统，以进一步了解可能的 外周退行性变/再生的潜在机制 品味系统。建议的研究将提供以下方面的新资料：1) 神经生理变化的性质，反应变化的部位， 味觉感受器细胞内转导元件的生物物理变化 神经切断加上饮食钠限制的结果，2) 免疫系统和神经活动在调节生理过程中的作用 影响，3)时间、去神经和饮食钠的影响 限制鼓索神经支配的稳定性和准确性 单个菌状乳头的模式，以及4)切片诱导的 膝状神经节细胞和鼓索纤维的数量。发现 从这些研究中将提供关于可塑性的更多信息 大鼠的外周味觉反应和神经解剖结构 正常和再生的成人外周味觉系统。他们还将 有助于确定饮食对再生神经和 感官感受器的功能和解剖学。

DESCRIPTION: (Adapted from applicant's abstract) The dependence of taste buds on the nerve fibers that innervate them has been used as a model to understand nerve/target interactions. Loss of innervation results in a loss of the normal morphological appearance of taste buds, while restoration of innervation results in a restoration of taste bud morphology and function. Therefore, the degenerating and regenerating peripheral gustatory system is ideal for studying dynamic biological processes in which progenitor cells ultimately form mature, functional cells capable of transducing taste information. Previous work in the laboratory of the Principal investigator showed that the adult regenerating gustatory system is especially susceptible to environmental manipulations. Combining unilateral chorda tympani nerve section and low sodium diet in adult rats results in a variety of functional and anatomical alterations in both taste buds and in the regenerating nerve. Furthermore, the effects are not limited to the sectioned side of the tongue because profound functional and anatomical alterations also occur in the intact, contralateral side. To extend these findings, neurophysiological taste responses from single geniculate ganglion cells will be recorded during manipulation of voltages across the lingual epithelium in vivo in control rats and in rats fed either a NaCl-replete or NaCl-deficient diet after unilateral sectioning of the chorda tympani nerve at adulthood. Coordinated morphological studies will examine a variety of processes involved with maintenance and regeneration of receptor cells and associated neural elements. Finally, the role of neural activity and of the immune system will be explored to further an understanding of possible underlying mechanisms involved in the degenerating/regenerating peripheral taste system. The proposed studies will provide new information about: 1) the nature of neurophysiological changes, the site of response alterations, and biophysical changes in the transducing elements in taste receptor cells as a result of nerve sectioning coupled with dietary sodium restriction, 2) the role of the immune system and neural activity in mediating physiological effects, 3) the effects of time, dennervation, and dietary sodium restriction on the stability and accuracy of chorda tympani innervation patterns in single fungiform papillae, and 4) section-induced changes in the numbers of geniculate ganglion cells and chorda tympani fibers. Findings from these studies will provide further information about the plasticity of peripheral taste responses and the neuroanatomical organization in the normal and regenerating adult peripheral gustatory system. They will also be useful in determining the role that diet has on regenerating nerves and on sensory receptor function and anatomy.