CARDIAC SENSORY INTEGRATION IN CERVICAL SPINAL CORD

颈脊髓的心脏感觉统合

• 批准号: 2872913
• 负责人: ROBERT D FOREMAN
• 金额: $ 25.49万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-02-01 至 2001-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2872913
• 关键词: Primates; cerebellum; chemical stimulation; coronary artery; coronary occlusion /thrombosis; myocardial ischemia /hypoxia; neural inhibition; pain; sensory mechanism; spinal cord; urinary bladder; vagus nerve; visceral afferent nerve

DESCRIPTION: The long term objective of the proposed research is to provide an understanding of the central neural integration that could explain production or suppression of pain associated with myocardial ischemia. The focus of the current set of experiments is to analyze a specific group of cells in the first cervical to third cervical spinal segments that could inhibit transmission in the spinothalamic tract. The hypothesis is that high cervical neurons with descending projections are involved in processing sensory visceral information that inhibits nociceptive inputs and distant spinal segments. Specific aims are designed to answer the following questions. 1) Does chemical stimulation or inactivation of neurons in high cervical segments affect activity of thoracic and lumbosacral spinothalamic tract neurons? 2) Are cervical propriospinal neurons excited by sensory visceral inputs that enter different spinal segments? 3) Does vagal stimulation excite cervical propriospinal neurons? 4) Are synaptic connections in medullary nucleus tractus solitarius needed for vagal effects in cervical neurons? 5) Are cervical propriospinal neurons excited by cardiac sensory information traveling in vagal fibers, sympathetic fibers or both types of afferent neural fibers? 6) Does myocardial ischemia affect activity of cervical propriospinal neurons? Neurophysiological techniques will be used to address these aims. In the first specific aim, extracellular potentials of thoracic and lumbosacral spinothalamic tract neurons will be recorded in monkeys to determine effects of stimulating or inactivating cervical neurons. In Specific Aims 2-6, extracellular potentials of cervical propriospinal neurons with projections to thoracic or lumbar segments will be recorded in monkeys to determine responses to visceral stimuli. The data derived from these studies will serve as a important basis for understanding the phenomenon of "silent" myocardial ischemia in humans. This project should provide insights into central neural mechanisms involved in suppression of visceral nociceptive information. Thus, these results are expected to provide a neurophysiological basis to explain the elevated pain threshold that is observed in patients who experience myocardial ischemia without pain and are at risk for sudden death.

描述：拟议研究的长期目标是 提供对中枢神经整合的理解 解释与心肌相关的疼痛的产生或抑制 缺血。 当前这组实验的重点是分析 第一颈椎至第三颈椎的特定细胞群 可以抑制脊髓丘脑束传播的片段。 假设是具有下降投射的高颈神经元 参与处理感觉内脏信息，抑制 伤害性输入和远处的脊髓节段。 具体目标旨在回答以下问题。 1) 是否 高颈段神经元的化学刺激或失活 影响胸腰骶脊髓丘脑束神经元的活动？ 2）颈部本体脊髓神经元是否受到内脏感觉输入的兴奋 进入不同的脊柱节段？ 3）迷走神经刺激会兴奋吗 颈椎固有脊髓神经元? 4) 突触连接是否 颈椎迷走神经效应所需的孤束核 神经元？ 5) 颈椎本体脊髓神经元是否受到心脏的兴奋？ 感觉信息在迷走神经纤维、交感神经纤维或两者中传播 传入神经纤维的类型？ 6）心肌缺血有影响吗 颈椎固有脊髓神经元的活动？ 神经生理学技术将用于实现这些目标。 在 第一个具体目标，胸腰骶细胞外电位 将记录猴子的脊髓丘脑束神经元以确定 刺激或灭活颈部神经元的作用。 具体来说 目标2-6，颈部本体脊髓神经元的细胞外电位 胸椎或腰椎段的投影将被记录在 猴子以确定对内脏刺激的反应。 这些研究得出的数据将作为重要基础 了解人类“无声”心肌缺血的现象。 该项目应该提供对中枢神经机制的见解 参与抑制内脏伤害性信息。 因此， 这些结果有望为以下方面提供神经生理学基础： 解释在以下患者中观察到的疼痛阈值升高 经历心肌缺血但无疼痛，并有突然发生心肌缺血的风险 死亡。