Intraglomerular Lateral Inhibition in the Olfactory Bulb

描述（由申请人提供）：这个项目的总体目标是确定主嗅球的输出是如何被这个结构的局部电路调节的。特别是，该建议侧重于研究侧抑制，这是神经回路中普遍存在的特征，被认为在决定刺激诱发反应的特异性和调节包括嗅球在内的许多大脑区域的网络动力学方面起着核心作用。更好地了解神经回路的功能特性，如侧抑制，对神经科学的许多领域至关重要，嗅球提供了一个有趣且易于处理的模型系统，用于研究有关神经回路调节神经活动的基本问题。这些实验旨在解决一个假设，即连接嗅球中与不同肾小球模块相关的主要神经元的抑制回路的一个功能是介导功能性侧抑制。具体来说，我们使用来自二尖瓣细胞的成对记录来研究突触回路的特性，这些突触回路使与不同肾小球相关的二尖瓣细胞之间产生功能连接。使用这种方法，我们将测试当二尖瓣细胞活动的频率与在气味刺激期间进行的体内记录的频率相似时，是否会发生对单个二尖瓣细胞之间的侧抑制。我们还将研究侧抑制连接的短期可塑性，并研究复发性和侧抑制的相互作用。综上所述，这些结果将为抑制回路在形成感觉表征中所起的作用提供重要的见解，特别是在嗅球中，以及理解抑制异常如何导致嗅球和其他大脑网络的功能缺陷。

DESCRIPTION (provided by applicant): The overall goal of this project is to determine how the output of the main olfactory bulb regulated by is the local circuitry of this structure. In particular, this proposal focuses on studying lateral inhibition, a ubiquitous feature of neuronal circuits thought to play a central role in determining the specificity of stimulus-evoked responses and in regulating network dynamics in many brain regions, including the olfactory bulb. Gaining a better understanding of functional properties of neural circuitry such as lateral inhibition is of central importance to many areas of neuroscience and the olfactory bulb presents an interesting and tractable model system in which to study fundamental questions about the regulation of neural activity by circuitry. These experiments are designed to address the hypothesis that one function of inhibitory circuitry connecting principal neurons associated with different glomerular modules in the olfactory bulb is to mediate a functional lateral inhibition. Specifically we use paired recordings from mitral cells to study the properties of synaptic circuits making functional connections between mitral cells associated with different glomeruli. Using this approach we will test whether lateral inhibition between pairs of individual mitral cells occurs when mitral cell activity is similar in frequency to what has been reported from in vivo recordings made during odor stimulation. We also will investigate short- term plasticity of lateral inhibitory connections, and study the interaction of recurrent and lateral inhibition. In conjunction these results will provide important insights into the role played by inhibitory circuits in shaping sensory representations, especially in the olfactory bulb and in understanding how abnormalities of inhibition can lead to functional deficits in the olfactory bulb and other brain networks.