DORSAL COLUMN NUCLEI PROJECTIONS TO THE INFERIOR OLIVE

背柱核投射到下橄榄

• 批准号: 3416660
• 负责人: HELEN H MOLINARI
• 金额: $ 7.37万
• 依托单位: ALBANY MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-01 至 1995-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3416660
• 关键词: antiantibody; biological signal transduction; brain mapping; cats; cell cell interaction; cerebellar nuclei; cerebellum; cerebral cortex; dorsal column; electron microscopy; gamma aminobutyrate; neuroanatomy; olivary body; radiotracer; somesthetic sensory cortex; spinal cord mapping; synapses

Lack of coordination results not only from lesions of structures such as the cerebellum, which ar generally thought to play an important role in controlling movement, but also from compromise of structures such as the dorsal columns and their relay, the dorsal column nuclei, that provide sensory information to the cerebellum. Information from the dorsal column nuclei reaches the cerebellum through a number of projections, most of which arise from widely scattered neurons that cannot be subjected to detailed experimental evaluation. Work from this laboratory has shown, however, that in cat the connection from the gracile portion of the dorsal column nuclei to the dorsal accessory subdivision of the inferior olive (DAO) constitutes not only a substantial source of somatosensory information for the cerebellum but one amenable to experimental manipulation. The DAO projection neurons in the gracile nucleus appear to preferentially signal contracts with external objects that occur at unexpected times during movement. The proposed electron microscopic experiments will investigate the anatomical substrates that underlie such signalling. The first experiment will determine the synaptic mechanisms through which the dorsal column fibers activated by external contact might interact with DAO projection neurons in the gracile nucleus. The DAO projection neurons will be identified with a retrograde tracer; synaptic inputs from the dorsal columns will be labeled with degeneration. Inhibitory elements that might regulate responsiveness of DAO projection neurons to these inputs will be identified using antibodies to the neurotransmitter GABA. The second experiment seeks to determine how inhibition of the DAO projection neurons might be achieved. This will be done by evaluating whether, and at what sites, putative GABAergic neurons adjacent to DAO projection neurons receive inputs that might signal the occurrence of either motor commands (the cerebral cortex) or contact with external objects (the dorsal columns). The data collected from these and other experiments in this laboratory will help determine how compromise of the dorsal columns and dorsal column nuclei might contribute to production of motor deficits and, ultimately, to a greater understanding of how sensory information is used to generate coordinated movement.

缺乏协调结果，不仅来自结构的病变 小脑，通常认为它在 控制运动，也来自诸如结构的妥协 背侧柱及其继电器，背柱核，可提供 给小脑的感官信息。 背面柱的信息 细胞核通过许多投影到达小脑，大多数 这是由广泛分散的神经元产生的 详细的实验评估。 该实验室的工作表明， 但是，在猫中，从背侧的侧面部分开始 下橄榄的背侧附件细分柱核 （DAO）不仅构成了体感的实质性来源 小脑的信息，但可以适合实验 操纵。 gracile核中的DAO投影神经元似乎优先 信号与出现意外情况发生的外部物体合同 在运动期间。 提出的电子显微镜实验将 研究基于此类信号的解剖底物。 这 第一个实验将确定突触机制 外部接触激活的背柱纤维可能与DAO相互作用 格式核中的投射神经元。 DAO投影神经元将 用逆行示踪剂识别；背面的突触输入 列将用变性标记。 抑制性元素可能 调节DAO投影神经元对这些输入的响应能力将是 使用对神经递质GABA的抗体鉴定。 第二个 实验试图确定如何抑制DAO投射神经元 可能会实现。 这将通过评估是否以及在什么 位点，与DAO投射神经元相邻的假定GABA能神经元 接收输入，可能会表明出现任何电动机命令 （大脑皮层）或与外部物体接触（背侧 列）。 从这些实验室中的这些和其他实验中收集的数据将 帮助确定背侧柱和背侧柱的妥协 细胞核可能有助于运动缺陷的产生，最终导致 对感官信息的生成方式有更深入的了解 协调的运动。