PLASTICITY OF THE REGENERATING TASTE SYSTEM

描述：（改编自申请人摘要）味觉的依赖性 支配它们的神经纤维上的芽被用作模型， 了解神经/目标相互作用。 失去神经支配导致 的正常形态外观的味蕾，而恢复 神经支配导致味蕾形态和功能的恢复。 因此，退化和再生的外周味觉系统是 是研究动态生物学过程的理想工具， 最终形成能够传递味觉的成熟功能细胞 信息. 曾在主要研究者实验室工作 表明，成年人的再生味觉系统，特别是 易受环境影响 联合单侧索 鼓室神经切断和低钠饮食可引起多种 在味蕾和大脑中的功能和解剖学改变 再生神经 此外，效果并不限于 因为深刻的功能和解剖学 改变也发生在完整的对侧。 扩展这些 单膝状体神经节的味觉神经生理学反应 在操纵舌上的电压期间记录细胞 在对照大鼠和喂食NaCl-充满或 单侧鼓索神经切断后的低NaCl饮食 在成年期。 协调的形态学研究将检查各种 与受体细胞的维持和再生有关的过程， 相关的神经元 最后，神经活动的作用， 免疫系统将被探索，以进一步了解可能的 参与退化/再生外周的潜在机制 味觉系统 拟议的研究将提供以下方面的新信息：1） 神经生理学变化的性质，反应改变的部位， 味觉感受器细胞中转导元件的生物物理变化 由于神经切片加上饮食钠限制，2） 免疫系统和神经活动在介导生理性 影响，3）时间、去神经支配和膳食钠的影响 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，和4）切片引起的变化， 膝状神经节细胞和鼓索纤维的数量。 结果 从这些研究将提供进一步的信息可塑性 周围味觉反应和神经解剖组织在 正常和再生的成年外周味觉系统。 他们还将 有助于确定饮食对神经再生的作用， 感觉感受器功能和解剖学的研究

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.