DEVELOPMENT OF THE SENSE OF TASTE

说明(改编自《调查员摘要》)：建议 涉及到外周和中央味觉的非常早期的发展 老鼠体内的系统。其中三个具体目标建立在原则的基础上 研究人员证明，味觉乳头将在体外形成 缺乏正常感觉的胚胎大鼠舌的器官培养 神经支配。具体目标1将确定 器官培养的发育与胚胎年龄的关系 组织。它将试图建立胚胎年龄阈值，并削减- 关了。特异靶2确定体内分子特征 舌头的数量在器官培养中得以保持。目标3决定效果 将舌头与味觉和非味觉共同培养 乳突上的神经节和体外味蕾的形成。具体目标4 5处理二级味觉神经元的发育和利用脑干 NST的切片，以探索神经元电路和 功能。特定目标4测试了这样的假设，即成人水平 NST神经元对兴奋性和抑制性的敏感性 神经递质是在出生后逐渐获得的。AIM 5测试 大鼠内源性神经递质特征的假说 NST细胞会因饮食缺钠而改变。这些是体外培养的 系统以前没有被用来研究味觉的发展，一个 影响食物选择和营养的感觉。

DESCRIPTION (Adapted from the Investigator's Abstract): The proposal deals with very early development of peripheral and central taste systems in the rat. Three of the specific aims build on the principal investigator's demonstration that taste papillae will form in vitro from organ cultures of the embryonic rat tongue lacking normal sensory innervation. Specific Aim 1 will determine the potential for development in organ culture as a function of the age of the embryonic tissue. It will attempt to establish embryo age thresholds and cut- offs. Specific Aim 2 determines if in vivo molecular characteristics of tongue are maintained in organ culture. Aim 3 determines the effects of co-culturing the tongue with gustatory and nongustatory sensory ganglia on papilla and taste-bud formation in vitro. Specific aims 4 nd 5 deal with second order taste neuron development and utilize brainstem slices of the NST to explore basic changes in neuron circuitry and function. Specific Aim 4 tests the hypothesis that the adult level of sensitivity of NST neurons to excitatory and inhibitory neurotransmitters is acquired gradually following birth. Aim 5 tests the hypothesis that intrinsic neurotransmitter characteristics of rat NST cells are altered by dietary sodium deprivation. These in vitro systems have not previously been used to study development in taste, a sense that influences food selection and nutrition.