STRUCTURE RELATIONSHIPS OF BRAINSTEM TASTE CELLS

描述（改编自研究者摘要）：发育 神经生物学家已经使用了许多模型来研究 感觉输入对中枢神经系统高级神经元成熟的影响。 这种强烈的努力并不奇怪，因为更好地理解 这些相互作用对于我们最终理解 大脑的正常发育，以及大脑对 损伤 据推测，发展中国家的形态 孤束嘴侧核（rNST）内的味觉神经元 大鼠是修改的，以响应性质的变化， 传入输入 并进一步提出， 对特异性促味剂最敏感的rNST神经元亚群可以 通过减少或增加动物暴露于 在出生后的早期有味道。 为了解决这些问题和相关问题， 假设，提出了两个主要的具体目标。 第一个目标 将是表征结构-功能的正常发展 大鼠rNST区味觉神经元的相互关系 这 信息将为第二个目标提供必要的基础， 这是为了确定改变一个组成部分的影响， 味觉环境对结构-功能发展的影响 在这个核心的关系。 拟议的研究将开始， 细胞内记录和标记技术，以确定 单个生理特征的rNST神经元的形态学 出生后第10、20-22和28-30天的大鼠。 每一个神经元都会被测试 它对一系列标准的味觉刺激的反应， 通过神经生物素的细胞内离子电渗注射。 标记的 神经元将受到三维定性和 定量分析，形态特征， 与生理反应特性相关， 结构-功能关系将与先前的结构-功能关系进行比较。 在成年动物中建立。 然后计划进行研究， 在两个独立的系列实验中，NST的正常味觉输入。 在第一个系列中，将采用Na剥夺模型来减少 NST神经元的NaCl相关输入。 在一个单独的系列， 实验中，选择性地增加 通过用0.01M灌洗口腔使动物暴露于一种促味剂 从出生起每天检查3次盐酸奎宁。 在 每种情况下的比较将在rNST的发展之间进行 结构-功能关系以及 正常的动物

DESCRIPTION (Adapted from the Investigator's Abstract): Developmental neurobiologists have employed numerous models to examine the influence of sensory inputs on the maturation of higher-order neurons in the CNS. This intense effort is not surprising, since a better comprehension of these interactions is essential to our ultimate understanding of the normal development of the brain, as well as the brain's response to injury. It is postulated that the morphology of the developing gustatory neurons in the rostral nucleus of the solitary tract (rNST) of the rat is modified in response to changes in the nature of the primary afferent input. It is further proposed that the morphology of specific subsets of rNST neurons that are most sensitive to specific tastants can be altered by decreasing or increasing the animal's exposure to that tastant during early postnatal life. To address these and related hypotheses, two principal Specific Aims are proposed. The first aim will be to characterize the normal development of structure-function relationships of gustatory neurons in the rNST of the rat. This information will provide the necessary foundation for the second aim, which is to determine the effect of altering one component of the gustatory environment on the development of structure-function relationships in this nucleus. Proposed research will begin by using intracellular recording and labeling techniques to determine the morphology of individual physiologically- characterized rNST neurons in rats on postnatal days 10, 20-22 and 28-30. Each neuron will be tested for its response to a standard series of taste stimuli and then labeled by intracellular iontophoretic injection of Neurobiotin. The labeled neurons will be subjected to three-dimensional qualitative and quantitative analysis, the morphological characteristics will be correlated with physiological response properties and the resultant structure-function relationships will be compared to those previously established in adult animals. Studies are then planned to alter the normal gustatory input to the NST in two separate series of experiments. In the first series, a Na-deprivation model will be employed to reduce the NaCl- related input to neurons in the NST. In a separate series of experiments, the developmental impact of selectively increasing the animal's exposure to one tastant by lavaging the oral cavity with 0.01M quinine hydrochloride 3 times each day from birth will be examined. In each case comparisons will be made between the development of rNST structure-function relationships and the relationships identified in normal animals.