The role of capsacin injury on nerve morphology & pain

辣椒素损伤对神经形态的作用

• 批准号: 6695357
• 负责人: JACOB P SCHWARZ
• 金额: $ 4.99万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6695357
• 关键词: C fiber; Schwann cells; afferent nerve; behavior test; capsaicin; cell morphology; confocal scanning microscopy; denervation; dorsal root; electrical measurement; hyperalgesia; laboratory rat; macrophage; nerve growth factors; nerve injury; nerve threshold; nociceptors; postdoctoral investigator; sodium channel; spinal ganglion; spinal nerves; thermoreception; tissue /cell culture; tumor necrosis factor alpha; wallerian degeneration

DESCRIPTION (provided by applicant): The mechanisms underlying neuropathic pain remain incompletely understood. Using a modification of the spinal nerve ligation model of Chung, have observed: 1) hyperalgesia is not reversed by dorsal rhizotomy, 2) spontaneous activity develops among C fibers of adjacent, uninjured roots, 3) prominent remodeling of Remak bundles containing surviving C fibers in distal branches. We hypothesize that selective lesion of L5 nerve leads to Wallerian degeneration distally and partial Remak bundle denervation. Remak, bundles react as if completely denervated and release excessive growth factors and cytokines. Intact L4 fibers transport these agents to nerve cell bodies they induce changes in excitability and hyperalgesia. In the proposed study, capsacin will be applied to the L5 mixed spinal root. This technique will provide a selective lesion of nociceptive afferents and elaborate the role of this lesion in hyperalgesia, Remak bundle remodeling, and spontaneous activity in the uninjured fibers. This will clarify neuropathic pain phenomena.

描述（由申请人提供）： 神经性疼痛的基础机制尚未完全理解。使用修改Chung的脊神经结扎模型，已经观察到：1）在背侧根茎切开术中不会逆转痛觉过敏，2）在相邻的，无损坏的根的C纤维之间会出现自发活动，3）含有Remak的重要重塑，这些重塑含有远处的C纤维纤维，这些重塑是遥远的C纤维纤维。我们假设L5神经的选择性病变会导致远端和部分Remak Bundle DeNervation的Wallerian变性。 Remak，束反应好像完全消除并释放了过多的生长因子和细胞因子。完整的L4纤维将这些药物运输到神经细胞体上，它们会引起兴奋性和痛觉过敏的变化。在拟议的研究中，辣椒素将应用于L5混合脊髓。该技术将提供伤害性传入的选择性病变，并详细说明这种病变在未受伤的纤维中的损伤，Remak束重塑和自发活动中的作用。这将阐明神经性疼痛现象。