Serotonergic modulation of taste

描述（由申请人提供）：本申请的目标是提供动物味觉心理物理学方面的专业培训，这是将味觉系统的神经生物学机制与行为评估的味觉功能联系起来不可或缺的领域。为了实现这一目标，实验将使用心理物理程序来评估血清素的药理调节对大鼠味觉引导行为的影响。影响摄入行为的药物通常被认为是通过调节食物和液体的味道的有益特性来实现的。了解这些药物的作用机制对于确定饮食行为中品味的享乐方面的作用至关重要，这无疑是导致这个国家日益严重的肥胖问题的原因。然而，在没有首先评估其对感觉辨别功能的影响之前，得出药物只影响味觉的享乐成分的结论还为时过早。血清素是一种无处不在的神经递质，它在大脑和与味觉和奖励有关的外围区域发挥作用。影响血清素传递的药物会影响食物和液体的摄入，并影响抑郁症和健康人的味觉感知。这在多大程度上是由品味的享乐性或歧视性方面造成的，还有待确定。本提案中的实验旨在明确测试血清素再摄取抑制剂和促进剂（因此分别是功能性激动剂和拮抗剂）对心理物理任务表现的剂量相关影响。这些任务评估对味觉刺激的检测、识别和享乐反应的浓度依赖性变化。在一个快速发展的理解味觉感知生理硬件的领域，需要精通行为技术的科学家将越来越多的关于味觉加工的神经生物学、细胞和分子机制的信息与它的最终共同输出-行为联系起来。

DESCRIPTION (provided by applicant): The goal ofthis application is to provide specialized training in animal taste psychophysics, a field which is indispensablle in linking neurobiological mechanisms of the gustatory system to behaviorally assessed taste function. To achieve this goal, experiments will be conducted using psychophysical procedures to assess the effects of pharmacological modulation of serotonin on taste-guided behavior in rats. Drugs that affect ingestive behavior are often assumed to do so by modulating the rewarding characteristics of the taste of foods and fluids. Understanding the mechanisms of action of these drugs is crucial to defining the role of the hedonic aspect of taste in eating behavior, which indisputably is contributing to this nation's growing problem with obesity. However, it is premature to conclude that a drug only affects hedonic components of taste without first assessing its effects on sensory-discriminative function. Serotonin is a ubiquitous neurotrasmitter that has actions in areas of the brain and periphery involved in taste and reward. Drugs that impinge on serotonergic transmission affect ingestion of food and fluid and impact taste perceptions in depressed and healthy humans. The extent to which this results from hedonic or discriminative aspects of taste has yet to be determined. The experiments in this proposal are designed to explicitly test the dose-related effect of an inhibitor and a facilitator of serotonin reuptake (and thus a functional agonist and antagonist, respectively) on performance in psychophysical tasks. These tasks assess concentration-dependent changes in the detection of, identification of, and hedonic responsiveness to taste stimuli. In a field advancing rapidly toward understanding the physiologic hardware of taste perception, scientists fluent in behavioral techniques are needed to link the growing body of information concerning the neurobiological, cellular, and molecular mechanisms of taste processing to its final common output - behavior. PUBLIC HEALTH RELEVANCE: The experiments in this proposal are designed to assess how drugs not only affect how "good" or "bad" something tastes, but also how strong it is and what it tastes like, independent of its rewarding or aversive characterisfics. These studies will help define how chemical signaling in the body affects taste-guided behavior (i.e., eating and drinking). This informafion may help clinicians understand and more effectively treat patients with eating disorders affected by the rewarding characteristics of taste (e.g., obesity) and psychiatric disorders in which taste percepfions are distorted (e.g., depression).