Synaptic Processing in the Olfactory System

描述：（申请人提供） 我们研究的长期目标是了解嗅觉是如何 信息是在哺乳动物的大脑中处理的。为了解决这个问题，我们 研究大鼠嗅球脑片神经元的特性--第一次 大脑中处理嗅觉信息的部位。虽然快速突触 大脑中的传递通常由神经递质释放介导 从轴突神经末梢，树突状递质的释放被认为是发挥作用， 在嗅球中的重要作用。主二尖瓣释放谷氨酸 细胞树突激发局部中间神经元，颗粒细胞， 进而释放γ-氨基丁酸（GABA）回到二尖瓣 树突这种树-树回路是自我抑制和侧抑制的基础 并被认为在气味中起着关键作用 嗅觉球的辨别和分辨能力。这个项目的主要目标是 一项研究计划是阐明 嗅细胞中僧帽细胞和颗粒细胞之间的树突状抑制 灯泡具体目标集中在表征的基本属性 两种细胞类型之间的传递，以及GABAB受体的作用 和调节树突信号的活性依赖性可塑性。二尖瓣和 用红外微分干涉光学观察颗粒神经元 （IR-DIC），并使用膜片钳记录技术进行研究。具体目标I 建议建立基本的量子机制， 突触偶联的二尖瓣和颗粒对之间的树突传递 细胞具体目标2提出研究GABAB受体在 树突状抑制我们假设代谢型GABAB受体 在调节二尖瓣和 颗粒细胞具体目标3提出研究突触可塑性， 树-树突触我们假设，兴奋性树突输入， 颗粒细胞表达活性依赖性长时程增强和抑制。 这些实验将提供新的见解突触机制 潜在的树-树传播，这是至关重要的 嗅觉信息在大脑中的处理。

DESCRIPTION: (provided by applicant) The long-term objective of our research is to understand how olfactory information is processed in the mammalian brain. To address this question, we study the properties of neurons in slices of the rat olfactory bulb-the first site in the brain where olfactory information is processed. While fast synaptic transmission in the brain is typically mediated by neurotransmitters released from axon nerve endings, dendritic transmitter release is thought to play an important role in the olfactory bulb. Glutamate released from principal mitral cell dendrites excites the dendrites of local interneurons, granule cells, which in turn release gamma-aminobutyric acid (GABA) back onto mitral dendrites. This dendrodendritic circuit underlies self- and lateral inhibition of mitral cells and has been suggested to play a critical role in odor discrimination and resolution in the olfactory bulb. The major goal of this research proposal is to elucidate the synaptic mechanisms governing dendrodendritic inhibition between mitral and granule cells in the olfactory bulb. The specific aims focus on characterizing the fundamental properties of transmission between the two cell types, as well as the role of GABAB receptors and activity-dependent plasticity in modulating dendritic signaling. Mitral and granule neurons are visualized with infrared differential interference optics (IR-DIC) and studied using patch-clamp recording techniques. Specific Aim I proposes to establish the basic quantal mechanisms governing the strength of dendritic transmission between synaptically coupled pairs of mitral and granule cells. Specific Aim 2 proposes to investigate the role of GABAB receptors in dendrodendritic inhibition. We hypothesize that metabotropic GABAB receptors play an important role in modulating dendritic interactions between mitral and granule cells. Specific Aim 3 proposes to investigate synaptic plasticity at dendrodendritic synapses. We hypothesize that excitatory dendritic inputs to granule cells express activity-dependent long-term potentiation and depression. These experiments will provide new insight into the synaptic mechanisms underlying dendrodendritic transmission, which is of critical importance in the processing of olfactory information in the brain.