ORGANIZATION OF THE SPINAL CORD

我们研究的长期目标是探索脊髓， 七鳃鳗的脑干作为功能组织的模型， 脊椎动物中枢神经系统中的神经元。 目前的具体目标 建议是确定中枢模式产生的神经基础， 七鳃鳗游泳和呼吸的明确行为。 细胞内记录和刺激将用于寻找候选人 产生器中间神经元，其既具有振荡膜电位， 引起腹根运动爆发的强度和时间的变化 在虚构的游泳中。 成对的细胞内电极将用于 确定这些候选发生器之间的单一突触相互作用 interneurons和以前确定的神经元，以构建一个渐进的 更完整的脊柱功能和形态电路图 产生游泳活动的索。 固有的起搏器特性， 包括钙依赖钾电导的作用，将在 用于游泳的候选生成器中间神经元 呼吸 候选发生器中间神经元的形态将是 通过细胞内过氧化物酶和染料标记测定。 的详细 中间神经元的类型、突触连接、膜 特性和定量生理参数将被整合， 构建可测试的模型，用于运动的中枢模式生成， 呼吸一种简单的脊椎动物。

The long term goal of our research has been to explore the spinal cord and the brain stem of the lamprey as models for the functional organization of neurons in the vertebrate CNS. The specific objective of the present proposal is to determine the neural basis for central pattern generation of the well-defined behaviors of swimming and breathing in the lamprey. Intracellular recording and stimulation will be used to find candidate generator interneurons which both have oscillatory membrane potentials and evoke changes in the intensity and timing of motor bursts in ventral roots during fictive swimming. Paired intracellular electrodes will be used to determine unitary synaptic interactions between these candidate generator interneurons and previously identified neurons to construct a progressively more complete functional and morphological circuit diagram of the spinal cord which produces swimming activity. Intrinsic pacemaker properties, including the role of Ca-dependent K conductance, will be tested in candidate generator interneurons for swimming and particularly for respiration. The morphology of candidate generator interneurons will be determined by intracellular peroxidase and dye marking. The detailed information of types of interneurons, synaptic connections, membrane properties, and quantitative physiological parameters will be integrated to construct testable models for central pattern generation of locomotion and breathing in a simpler vertebrate.