Spinal Motor Conduction and Recovery After Human SCI

描述（由申请人提供）：本项目的目的是更好地了解创伤性损伤后人类脊髓内可塑性的自然史，特别关注自主神经系统内的变化以及这些变化如何影响痉挛的发展。进一步的目标是更好地了解神经学不完全性脊髓损伤（SCI）患者皮质脊髓束轴突内传导恢复的机制。这些信息可能有利于受试者的选择，结果测量的选择，以及对治疗人类SCI的新干预措施进行临床试验的结果的解释。我们将招募150名患有急性创伤性SCI的受试者，他们已入住锡拉丘兹大学医院。整个研究将持续5年。每例受试者将重复研究约2年。在每次评价时，将通过手动肌肉测试和表面EMG测量来评估随意收缩能力。脊髓兴奋性将用各种反射测量。应用特定的感觉输入和记录心率变异性，血压和其他措施将检查交感神经活动。将特别强调建立自主神经反射异常发展的时间过程，这是颈部和高胸SCI的潜在致命后果，其机制尚不清楚，但我们认为是由于脊髓中的异常发芽。皮质脊髓束传导将使用一种新的超高频经颅磁刺激装置，结合对单个运动单位放电特性的详细分析进行检查。在某些情况下，将测试K通道阻滞剂4-氨基吡啶的缓释制剂对传导的影响。

DESCRIPTION (provided by applicant): The purpose of this project is to gain a better understanding of the natural history of plasticity within the human spinal cord following traumatic injury, paying particular attention to changes within the autonomic nervous system and how these influence the development of spasticity. A further goal is to better understand the mechanisms underlying the recovery of conduction within axons of the corticospinal tract in persons with neurologically-incomplete spinal cord injury (SCI). This information may benefit subject selection, choice of outcome measures, and interpretation of findings as new interventions for treating human SCI make their way to clinical trials. We will recruit 150 subjects who have been admitted to University Hospital in Syracuse with acute, traumatic SCI. The overall study will last 5 years. Each subject will be studied repeatedly for a period of approximately 2 years. At each evaluation, voluntary contraction ability will be assessed with manual muscle testing and surface EMG measures. Spinal cord excitability will be measured with a variety of reflexes. Applying specific sensory inputs and recording heartrate variability, blood pressure, and other measures will examine sympathetic activity. Special emphasis will be placed on establishing the time-course of autonomic dysreflexia development, a potentially-lethal consequence of cervical and high-thoracic SCI whose mechanism is poorly understood, but which we believe is due to aberrant sprouting in the spinal cord. Corticospinal tract conduction will be examined using a novel ultra high frequency transcranial magnetic stimulation device coupled with detailed analysis of single motor unit discharge properties. A slow-release formulation the K-channel blocker 4-aminopyridine will be tested for its effects on conduction in some cases.