Potential long-term benefits of acute hypothermia after spinal cord injury: assessments with somatosensory-evoked potentials.
Potential long-term benefits of acute hypothermia after spinal cord injury: assessments with somatosensory-evoked potentials.
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DOI：
10.1097/ccm.0b013e318232d97e
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发表时间：
2012-02
影响因子：
8.8
通讯作者：
All AH
中科院分区：
文献类型：
--
作者：
Maybhate A;Hu C;Bazley FA;Yu Q;Thakor NV;Kerr CL;All AH
低温的神经保护作用是近二十年来的重要研究课题。在脊髓损伤（SCI）的动物模型中，主要的焦点是评估低温对行为和组织学结果的影响。虽然一些研究已经调查了电生理学的变化，在下降的运动通路与运动诱发电位记录在冷却过程中，我们在这里报告，低温诱导增加的电传导在脊髓上行通路与体感诱发电位（SSEPs）在受伤的大鼠。在我们的实验中，这些效果在急性低温后持续很长时间，并伴随着运动运动的潜在长期改善。实验室调查大学医学院。21只雌性刘易斯大鼠。体温过低。所有动物均接受了脊髓挫伤，使用NYU-撞击器，在胸椎T8处通过12.5 mm的重量下降。A组（n=10）随机分配全身2小时。低温发作（32±0.5°C）在损伤后约2.0小时开始。11只大鼠为对照组，伤后体温维持在37±0.5°C 2小时。两组均于伤前、伤后每周（至4周）进行SSEP记录和标准运动行为测试（BBB）。在损伤后第3天和第28天，将每组中随机选择的三只大鼠安乐死，用于组织学分析。与对照组相比，低温组显示出明显更高的SSEP振幅损伤后，与更长的潜伏期。亚低温组伤后即刻及4周后BBB评分均高于对照组。重要的是，低温组中BBB评分的特定变化（在对照组中未观察到）表明恢复了对运动控制至关重要的功能。组织学评价显示低温组组织保存更好。SCI后，早期全身低温通过改善大鼠的感觉电生理信号在损伤后数周提供了显著的神经保护作用。这是伴随着较高的运动行为评分和更多的备用组织在急性和急性期后受伤。
Neuroprotection by hypothermia has been an important research topic over last two decades. In animal models of spinal cord injury (SCI), the primary focus has been assessing effects of hypothermia on behavioral and histological outcomes. While a few studies have investigated electrophysiological changes in descending motor pathways with motor evoked potentials recorded during cooling, we report here, hypothermia induced increased electrical conduction in the ascending spinal cord pathways with somatosensory evoked potentials (SSEPs) in injured rats. In our experiments these effects lasted long after the acute hypothermia and were accompanied with potential long term improvements in motor movement. Laboratory Investigation. University Medical School. 21 Female Lewis Rats. Hypothermia. All animals underwent spinal cord contusion, with the NYU-Impactor, by a 12.5mm weight drop at thoracic vertebra T8. A group (n=10) was randomly assigned for a systemic 2hr. hypothermia episode (32±0.5°C) initiated ~2.0hrs post-injury. 11 rats were controls with post-injury temperature maintained at 37±0.5°C for 2hrs. The two groups underwent pre-injury, weekly post-injury (up to 4wks) SSEP recordings and standard motor behavioral tests (BBB). Three randomly selected rats from each group were euthanized for histological analysis at post-injury Day 3 and Day 28. Compared to controls, the hypothermia group showed significantly higher SSEP amplitudes post-injury; with longer latencies. The BBB scores were also higher immediately after injury and 4 weeks later in the hypothermia group. Importantly, specific changes in the BBB scores in hypothermia group (not seen in controls) indicated regained functions critical for motor control. Histological evaluations showed more tissue preservation in hypothermia group. Post-SCI, early systemic hypothermia provided significant neuroprotection weeks after injury via improved sensory electrophysiological signals in rats. This was accompanied by higher motor behavioral scores and more spared tissue in acute and post-acute periods after injury.