AMPA RECEPTOR MEDIATED SPINAL CORD OLIGODENDROCYTE DEATH

AMPA 受体介导的脊髓少突细胞死亡

• 批准号: 2036482
• 负责人: JOHN W MCDONALD
• 金额: $ 7.34万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-12-01 至 2000-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2036482
• 关键词: AMPA receptors; NMDA receptors; apoptosis; axon; calcium flux; disease /disorder model; electron microscopy; electrophysiology; genetically modified animals; immunocytochemistry; inhibitor /antagonist; kainate; laboratory mouse; laboratory rat; light microscopy; necrosis; neurons; neurotoxins; oligodendroglia; receptor expression; receptor sensitivity; spinal cord injury; stereotaxic techniques; tissue /cell culture; western blottings

Spinal cord trauma causes extended neurologic disability, with limited treatment options, and serious social and economic consequences. Both gray and white matter damage contribute to functional disability. While recent studies have begun to identify mechanisms contributing to neuronal injury, mechanisms underlying oligodendrocyte (oligo) or axonal injury remain unclear. Understanding the mechanisms of oligo death, and the subsequent consequences relative to neuronal and axonal injury and recovery, and behavioral outcome, could provide valuable clues to novel therapies for spinal cord injury and, possibly, other neurologic diseases such as stroke. The major objective of this proposal is to systematically study excitotoxic, AMPA receptor-mediated death of oligos in vitro and determine the relative role of this mechanism in spinal cord trauma. Extracellular glutamate is known to be elevated to high levels consequent to spinal cord trauma. Our preliminary evidence suggests that oligos express high levels of AMPA-type glutamate receptors, and can be destroyed by moderate overactivation of these AMPA receptors. Expression of functional AMPA-type glutamate receptors will be examined by western blots, immunohistochemistry, dye physiology, and electrophysiology in primary culture. The hypothesis that oligos in vitro and in vivo can be destroyed by toxic overactivation of AMPA receptors will be demonstrated pharmacologically by direct application of glutamate, and AMPA receptor specific agonists and antagonists in primary culture and in vivo spinal cord preparation. The nature of AMPA receptor-mediated oligo death, necrosis vs apoptosis, will be characterized in vitro by dy physiology, EM cellular morphology, and susceptibility in Bax knock-out and Bcl-2 over-expressing murine cultures. Finally, the hypothesis that blockade of AMPA receptor- mediated oligo death will reduce white matter damage in rat model of spinal cord trauma will be tested by selective application of AMPA receptor antagonists, and studying the possible relation of oligo death and neuronal injury. The effects of these manipulations on behavioral outcome from spinal cord trauma will be assessed. If our hypothesis correct, measures directed at reducing AMPA receptor-mediated oligo death may be useful in the acute treatment of spinal cord injury.

脊髓损伤会导致长期的神经功能障碍，但影响有限 治疗方案以及严重的社会和经济后果。 两个都 灰质和白质损伤会导致功能障碍。尽管 最近的研究已开始确定有助于 神经元损伤、少突胶质细胞 (oligo) 或轴突的潜在机制 伤势尚不清楚。 了解寡核苷酸死亡的机制，以及 与神经元和轴突损伤相关的后续后果以及 恢复和行为结果可以为小说提供有价值的线索 脊髓损伤和其他神经系统损伤的治疗 中风等疾病。 该提案的主要目标是 系统地研究兴奋毒性、AMPA 受体介导的寡核苷酸死亡 体外并确定该机制在脊柱中的相对作用 脊髓损伤。 已知细胞外谷氨酸升高至高水平 脊髓损伤导致的水平。 我们的初步证据 表明寡核苷酸表达高水平的 AMPA 型谷氨酸 受体，并且可以通过这些 AMPA 的适度过度激活而被破坏 受体。 功能性 AMPA 型谷氨酸受体的表达将 通过蛋白质印迹、免疫组织化学、染料生理学和 原代培养中的电生理学。 寡核苷酸的假设 体外和体内均可被 AMPA 的毒性过度激活所破坏 受体将通过直接应用在药理学上得到证明 谷氨酸和 AMPA 受体特异性激动剂和拮抗剂 原代培养和体内脊髓制备。 AMPA 的性质 受体介导的寡核苷酸死亡，坏死与凋亡，将是 在体外通过 dy 生理学、EM 细胞形态学和 Bax 敲除和 Bcl-2 过表达小鼠的易感性 文化。最后，阻断 AMPA 受体的假设 - 介导的寡核苷酸死亡将减少大鼠模型中的白质损伤 脊髓损伤将通过选择性应用 AMPA 进行测试 受体拮抗剂，并研究寡核苷酸死亡的可能关系 和神经元损伤。 这些操纵对行为的影响 将评估脊髓创伤的结果。 如果我们的假设 正确，旨在减少 AMPA 受体介导的寡核苷酸的措施 死亡可能有助于脊髓损伤的急性治疗。