Local Connections and in Vivo Physiology of Inhibitory Cortical Neurons.

描述(由申请人提供)：这是我的NIH独立之路奖(4 R00DA023700)的竞争性修订申请，以回应NIH资金通知(NOT-OD-09-058，NIH宣布可用于竞争性修订申请的恢复法资金)。尽管对大脑皮层环路的基本蓝图有广泛的了解，但对局部大脑皮层环路的详细知识、特定细胞类型的连通性及其功能仍然有限。这些研究最初建议研究兴奋性和抑制性突触输入大脑皮层特定类型的抑制性神经元的层状和细微尺度的特异性，并在体内检测不同类型的抑制性细胞的生理学及其对皮质活动的参与和调节。通过将全细胞记录与脑片扫描激光光刺激相结合，我们已经实现了检查不同细胞类型的功能输入的层状特异性的目标。我们还在了解特定抑制性细胞类型的体内生理学方面取得了进展。最近，我们开发了一种技术，通过电压敏感染料成像和激光扫描光刺激的新组合，能够在脑片上进行高分辨率和快速的功能成像。这一创新将在皮质回路研究领域产生广泛影响，因为它有助于快速绘制和精确评估皮质组织和功能。这项创新将能够通过检查抑制细胞类型对光刺激引起的神经元群体活动的影响并通过电压敏感染料成像检测到它们，从而能够映射抑制细胞类型的抑制输出。鉴于我最初的项目取得了令人兴奋的进展，我想修改我的最初目标，专注于进一步改进新技术，并将这种技术扩展到阐明大脑回路。新修订的具体目标是：(1)完善和改进高分辨率和快速的脑切片功能成像技术；(2)使用新技术绘制特定类型抑制性神经元的抑制输出图；(3)利用新技术表征多巴胺受体基因敲除(D2R-/-)小鼠的电路变化。这一修订请求支持购买额外的设备和培训一名少数民族研究生。 公共卫生相关性：对涉及特定抑制性细胞类型的皮质回路的详细组织的研究对于理解皮质功能是必要的。这些研究对人类健康具有重要意义，因为这些细胞类型及其活动参与了许多疾病模型，并可以介导与药物成瘾和滥用有关的皮质机制。

DESCRIPTION (provided by applicant): This is a competitive revision application for my NIH Pathway to Independence Award (4 R00DA023700) tilted "Local Connections and In Vivo Physiology of Inhibitory Cortical Neurons", in response to the NIH funding notice (NOT-OD-09-058, NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications). Despite extensive knowledge of the basic blueprint of cortical circuits, detailed knowledge about local cortical circuits, the connectivity of specific cell types and how they function is still limited. The studies originally proposed investigate the laminar and fine-scale specificities of excitatory and inhibitory synaptic input to specific types of inhibitory neurons in the cerebral cortex, and examine in vivo physiology of distinct inhibitory cell types and their participation and regulation of cortical activities. We have accomplished the aims of examining the laminar specificity of functional input to distinct cell types by combining whole cell recordings with scanning laser photostimulation in brain slices. We also have progressed toward understanding in vivo physiology of specific inhibitory cell types. Recently, we have developed a technique enabling high-resolution and fast functional imaging in brain slices through a novel combination of voltage sensitive dye imaging and laser scanning photostimulation. This innovation will have broad impacts in the field of cortical circuitry studies, as it facilitates rapid mapping and precise evaluation of cortical organization and function. The innovation will enable the ability to map inhibition output from inhibitory cell types by examining their influence on neuronal population activities evoked by photostimulation and detected by voltage sensitive dye imaging. Given the exciting developments of my original projects, I would like to revise my original aims, and focus on further improving the new technique and extending such technology toward elucidating cortical circuitry. The newly revised Specific Aims are to (1) Refine and improve the high-resolution and fast functional imaging technique in brain slices; (2) Map inhibitory output of specific types of inhibitory neurons using the novel technique; (3) Characterize circuit alterations in dopamine receptor knockout (D2R-/-) mice with the novel technique. This revision requests support to purchase additional equipment and train one minority graduate student. PUBLIC HEALTH RELEVANCE: Studies of the detailed organization of cortical circuits involving specific inhibitory cell types are necessary toward understanding cortical function. These studies have important implications for human health, as these cell types and their activities are involved in many disease models and can mediate the cortical mechanisms related to drug addiction and abuse.