Sympathetic control of cutaneous blood flow and blood pressure in human spinal cord injury

人类脊髓损伤中皮肤血流和血压的交感神经控制

• 批准号: nhmrc : 400961
• 负责人: Prof Vaughan Macefield
• 金额: $ 16.14万
• 依托单位: University of Western Sydney
• 依托单位国家: 澳大利亚
• 项目类别: NHMRC Project Grants
• 财政年份: 2006
• 资助国家: 澳大利亚
• 起止时间: 2006-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/sympathetic-control-cutaneous-cord-injury/99543
• 关键词: Sympathetic; control; cutaneous; blood; flow

While spinal cord injury can cause devastating changes in the nervous system paralysis and loss of sensation relatively little is known about changes to the sympathetic nervous system. The sympathetic nervous system is intimately involved in the ongoing control of blood pressure, blood flow and temperature control. Loss of sympathetic control can occur following spinal cord injury. Interruption of descending pathways can result in partial or complete loss of sympathetic outflow from the thoracolumbar segments. Complete decentralization can result in autonomic dysreflexia (autonomic hyperreflexia), in which sensory stimuli originating below the lesion evoke a reflex increase in sympathetic drive to the blood vessels, causing them to constrict. Because of this, blood pressure may rise suddenly and remain at such high levels that stroke and (occassionally) cardiac arrest may occur. This phenomenon, autonomic dysreflexia, is considered a medical emergency. The typical subjective signs of autonomic dysreflexia include a throbbing headache, tingling in the head or nasal congestion; sweating and flushing above the lesion are clinical signs that prompt medical staff to measure blood pressure and to locate the source of sensory irritation (usually a distended bladder or impacted colon, sometimes a pressure sore or ingrown toenail). Commonly, however, subclinical episodes go undetected, and this phenomenon of silent dysreflexia is of increasing concern. This project will develop means of assessing the integrity and state of the sympathetic nervous system below a lesion in patients with spinal cord injury and characterize the firing properties of reflexly activated sympathetic neurones.

虽然脊髓损伤会导致神经系统瘫痪和感觉丧失的破坏性变化，但人们对交感神经系统的变化知之甚少。交感神经系统密切参与血压、血流和温度的持续控制。脊髓损伤后可能会失去交感神经控制。下行通路的中断可能导致胸腰段交感神经流出部分或完全丧失。完全去中心化可导致自主神经反射障碍（自主神经反射亢进），其中源自病变下方的感觉刺激引起交感神经驱动血管的反射性增加，导致血管收缩。因此，血压可能会突然升高并保持在很高的水平，从而可能发生中风和（偶尔）心脏骤停。这种现象称为自主神经反射异常，被认为是一种医疗紧急情况。自主神经反射异常的典型主观症状包括搏动性头痛、头部刺痛或鼻塞；病变上方出汗和潮红是临床症状，提示医务人员测量血压并找到感觉刺激的来源（通常是膀胱扩张或受影响的结肠，有时是压疮或嵌趾甲）。然而，亚临床发作通常未被发现，这种无声反射异常现象越来越引起人们的关注。该项目将开发评估脊髓损伤患者病变下方交感神经系统完整性和状态的方法，并表征反射激活交感神经元的放电特性。