Behavioral and Physiological Mechanisms of Olfaction

描述（由申请人提供）：本提案将侧重于使用蜜蜂（意大利蜜蜂）作为模型动物物种，以了解对气味的行为可塑性机制。这些动物面临着与哺乳动物相同类型的嗅觉问题。它们需要检测和响应大量气味的能力，因为它们依赖于定位许多不同类型的花来收获花蜜中的碳水化合物资源。这些气味与花蜜的关联在个体的一生中会发生多次变化，这也要求动物了解这些关联。和哺乳动物一样，昆虫也有各种各样的方式来学习和编码对花香的记忆。比较证据表明，昆虫和哺乳动物之间的行为和系统水平的神经处理相似性是独立进化的。这表明，可能只有一种通用的神经解决方案可用于编码有关气味的信息。因此，作为比较模型，昆虫对于揭示气味如何在CNS中学习和编码以及这种机制是否是嗅觉处理的基础至关重要。该建议的目的是评估存在于昆虫嗅叶（AL）中的神经可塑性机制，其是哺乳动物嗅球的神经类似物（Hildebrand & Shepherd 1997）。中心主题是，记录的神经机制和调节途径，在AL代表的存在（或不存在）的强化作为一种手段，以过滤掉不重要的，可变的背景气味。这使得生物学相关的，学习的气味很容易被检测到。将有三个目标。首先，行为调查将详细研究机制，基础上的学习注意力不集中（CS预暴露效应）对气味和阻塞的气味气味混合物。特别是，操作的条件反射的情况下，将揭示在何种程度上，具体的理论治疗CS预暴露可以占它在昆虫。第二，多通道记录技术将被用来调查是否以及如何这些行为机制可能会被实施为一个过滤机制在AL。第三，药理学和分子操作的RNA干扰的方式将被用来检查如何调节途径代表强化AL通过调节生物胺（5-羟色胺和章鱼胺）的释放。

DESCRIPTION (provided by applicant): This proposal will focus on using the honeybee (Apis mellifera) as a model animal species for understanding mechanisms of behavioral plasticity toward odors. These animals are faced with the same types of olfactory problems as mammals. They require the capability to detect and respond to a very large number of odors because they depend on locating many different types of flowers to harvest carbohydrate resources in nectars. Association of these odors with nectar changes many times within an individual's lifetime, which also requires that animals learn about these associations. Like mammals, insects exhibit a variety of means to learn about and encode memories for floral odors. Comparative evidence indicates that behavioral and systems-level neural processing similarities between insects and mammals have evolved independently. That suggests that there may only be one general neural solution available to encode information about odors. Therefore, as comparative models, insects can be critical for revealing how odors are learned and encoded in the CNS, and whether this mechanism is fundamental to olfactory processing. The aims of this proposal are to evaluate mechanisms of neural plasticity that exist in the insect Antennal Lobes (AL), which are the neural analogs to the mammalian Olfactory Bulb (Hildebrand & Shepherd 1997). The central theme is that documented neural mechanisms and modulatory pathways in the AL that represent the presence (or absence) of reinforcement serve as a means to filter out unimportant, variable background odors. This allows biologically relevant, learned odors to be readily detected. There will be three aims. First, behavioral investigations will examine in detail mechanisms that underlie a learned inattention (CS preexposure effect) toward odors and blocking in odor-odor mixtures. In particular, manipulations of the conditioning context will reveal the extent to which specific theoretical treatments of CS preexposure can account for it in insects. Second, multichannel recording techniques will be employed to investigate whether and how these behavioral mechanisms may be implemented as a filtering mechanism in the AL. Third, pharmacological and molecular manipulation by way of RNA interference will be used to examine how modulatory pathways represent reinforcement in the AL by regulating biogenic amine (serotonin and octopamine) release.