GROUP II INTERNEURON ACTIONS IN LOCOMOTION & MICTURITION

第二组中间神经元运动动作

• 批准号: 6230894
• 负责人: DAVID A MCCREA
• 金额: $ 22.5万
• 依托单位: UNIVERSITY OF MANITOBA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-21 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6230894
• 关键词: action potentials; afferent nerve; cats; chordate locomotion; electrophysiology; electrostimulus; immunocytochemistry; interneurons; microelectrodes; motor neurons; muscle function; neural transmission; neuroanatomy; neuroregulation; neurotransmitters; single cell analysis; somatic reflex; spinal reflex; urination

Description: Neuronal circuitry in the spinal cord generates the basic pattern of rhythmic flexion and extension during locomotion. This activity is modified during movement by information about the length of muscles sent to the spinal cord from peripheral receptors. Feedback adapts the spinal motor output to changing conditions and ensures smooth movements. This proposal will locate and identify new classes of spinal cord interneurons activated by group II muscle spindle afferents signaling static muscle length. Despite the powerful effects of the group II reflex system in controlling movements, relatively little is known about the activity of spinal interneurons receiving group Il feedback during locomotion. Electrophysiological recordings will be used to locate and determine the synaptic connectivity of group II responsive interneurons in the lumbo-sacral spinal cord. The spontaneous and evoked activity of these interneurons will be determined during fictive locomotion in decerebrate adult cats. The aims include determining whether mid-lumbar group II interneurons, active during flexion, are inhibitory or excitatory to motoneurons. Stimulation of certain group II afferents promotes flexion while stimulation of group II afferents in other nerves promotes extension. To determine involvement of interneurons in either of these reflex pathways, the activity and responses of interneurons excited by these nerves will be assessed during peripheral nerve stimulation that perturbs the step cycle. Other experiments will examine the involvement of sacral interneurons believed to suppress group II and cutaneous afferent transmission during micturition and locomotion. Anatomical reconstruction of intracellularly stained interneurons will be used to determine the extent of their axonal projections and immunohistochemistry will be used to determine neurotransmitters associated with these interneurons.

描述：脊髓中的神经元电路产生基本模式 运动期间的节奏屈曲和延伸。此活动已修改 在通过有关发送到脊柱的肌肉长度的信息移动期间 来自外围受体的绳子。反馈使脊柱电机输出适应 改变条件并确保流动的流动。该建议将定位，并 确定由II组肌肉激活的新类脊髓中间神经元 主轴传入信号传递静态肌肉长度。尽管有强大的影响 在控制运动时，II组反射系统的相对较少 知道接收组IL反馈的脊柱中间神经元的活性 在运动期间。电生理记录将用于定位和 确定II组响应性中间神经元的突触连通性 腔骨脊髓。这些的自发和诱发活动 中间神经元将在小脑成人的虚拟运动期间确定 猫。目的包括确定中左右II组中间神经元是否 在屈曲过程中活跃，对运动神经元具有抑制作用或兴奋性。刺激 某些II组的传入促进了屈曲，同时刺激了II组 其他神经中的传入会促进延伸。确定参与 这两个反射途径中的任何一个中间神经元， 这些神经激发的神经元将在周围神经期间评估 刺激逐步周期。 其他实验将检查s骨中间神经元的参与 抑制II组和在排尿期间的皮肤传播传播 运动。细胞内染色中间神经元的解剖学重建 将用于确定其轴突预测的程度和 免疫组织化学将用于确定相关的神经递质 使用这些中间神经元。