cerebellar Afferent Integration Studied In Vitro

小脑传入整合的体外研究

• 批准号: 7082822
• 负责人: MICHAEL ARIEL
• 金额: $ 23.24万
• 依托单位: SAINT LOUIS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-15 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7082822
• 关键词: Chelonia; bioimaging /biomedical imaging; brain imaging /visualization /scanning; brain mapping; central neural pathway /tract; cerebellar Purkinje cell; cerebellar cortex; dyes; electrostimulus; gamma aminobutyrate; granule cell; mossy fiber; neural information processing; olivary body; optics; organ culture; vestibular pathway; visual stimulus

DESCRIPTION (provided by applicant): The cerebellar cortex (Cb) is a continuous neural layer of gray matter made up of identical repeating processing modules. Although the circuitry of these modules is similar for all vertebrates, the cortical surface is highly foliated in birds and mammals with complex regional specializations. Therefore, an analysis of Cb topography and its function is difficult because only a small fraction of cortical area is observed on the exposed folial surface. We posit that a radial system of inputs onto Purkinje cells from segregated Cb afferents and ascending granule cell axons is the primary processing unit of the Cb module. This primary system is acted on by a secondary, orthogonal system of parallel fibers and inhibitory interneurons. The proposed study will test this hypothesis with a unique in vitro turtle Cb preparation with the brainstem and sensory nerves attached. The primary advantage of the flat turtle Cb is that it is thin enough to permit optical recordings of the entire Cb surface during trans-illumination. Using voltage-sensitive absorbance dyes, Cb topography can be characterized from large responses to individual sensory stimuli. The small cortical size also permits a topographic anatomical analysis of afferent inputs based on a complete reconstruction of serial sections. Optical recording and pathway tracing experiments will be performed to reveal how sensory afferents map onto the Cb and how these different maps overlap. This project will focus on the effects of visual and vestibular afferents by measuring optical responses in vitro to natural stimulation or electrical microstimulation within the brainstem. Additional experiments will examine the basic cerebellar module: mossy fiber inputs, the radial and orthogonal axonal outputs of the granule cell and the convergence of excitatory and inhibitory inputs onto the Purkinje cell. Finally, climbing fiber inputs to Cb will be measured anatomically and physiologically to understand their role in plasticity and modulation of information flow through the basic cerebellar module. This in vitro preparation will thereby provide a unique model system for the study of learning and adaptation of motor behaviors.

描述（由申请人提供）：小脑皮质（Cb）是由相同的重复处理模块组成的连续灰质神经层。虽然这些模块的电路是类似的所有脊椎动物，皮质表面是高度叶状的鸟类和哺乳动物复杂的区域专业化。因此，Cb地形和其功能的分析是困难的，因为只有一小部分的皮质面积上观察到暴露的叶表面。 我们认为，从分离的Cb传入传入纤维到浦肯野细胞的放射状输入系统， 上行颗粒细胞轴突是Cb模块的主要处理单元。这个初级系统由平行纤维和抑制性中间神经元的次级正交系统作用。拟议的研究将测试这一假设与一个独特的体外龟Cb制备与脑干和感觉神经连接。平龟Cb的主要优点是它足够薄，允许在透射照明期间对整个Cb表面进行光学记录。使用电压敏感的吸收染料，Cb拓扑结构的特点是从大的个人感官刺激的反应。小的皮质尺寸也允许基于连续切片的完整重建的传入输入的地形解剖分析。 光学记录和路径追踪实验将揭示如何感觉传入映射到Cb和这些不同的地图如何重叠。本项目将通过测量脑干内对自然刺激或电微刺激的体外光学反应来关注视觉和前庭传入的影响。额外的实验将检查小脑的基本模块：苔藓纤维的输入，径向和正交轴突输出的颗粒细胞和浦肯野细胞的兴奋性和抑制性输入的收敛。最后，爬行纤维输入到Cb将被测量解剖学和生理学，以了解他们的作用，通过基本小脑模块的可塑性和调制的信息流。因此，这种体外制备将为运动行为的学习和适应的研究提供独特的模型系统。