Kohno Hiroki, Ishida Atsushi, Imamaki Mizuho, Shimura Hitoshi, Miyazaki Masaru
Department of General Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan.
Ann Vasc Surg. 2007 May;21(3):352-9. doi: 10.1016/j.avsg.2007.01.010.
Prevention of paraplegia remains an imperative issue in thoracoabdominal aortic surgery. The aim of this study was to assess the efficacy of a prophylactic magnesium infusion in a rat spinal cord ischemia model and to demonstrate spinal blood flow increase caused by the infusion. The study was conducted in two parts. Firstly, the neuroprotective effect of magnesium was assessed using a rat model with two different ischemic times: 10 min and 14 min. Spinal cord ischemia was induced by occlusion of the descending aorta. Rats in the treatment group were given a 100 mg/kg magnesium sulfate infusion before ischemia. Secondly, relative changes in spinal cord blood flow before and during ischemia were recorded using the laser Doppler flowmetry technique. Changes in blood flow were compared between the magnesium and control groups. Rats pretreated with magnesium showed good overall recovery after both 10 min (incidence of paraplegia 62.5% control vs. 37.5% Mg, n = 8 each) and 14 min (85.7% control vs. 57.1% Mg, n = 7 each) of ischemia, although the differences compared with controls were statistically insignificant. However, the magnesium group showed significantly better neurological performance during the early postischemic period. Comparison of changes in spinal circulation revealed less reduction in blood flow during ischemia in the magnesium-treated group. In conclusion, magnesium may have potential prophylactic benefits during ischemia by exerting a neuroprotective effect through vasodilation of the spinal cord vasculature. To our knowledge, this vasodilatory effect on the spinal cord has not previously been investigated. Optimization of the treatment regimen, however, is required.
在胸腹主动脉手术中，预防截瘫仍然是一个至关重要的问题。本研究的目的是评估预防性输注镁在大鼠脊髓缺血模型中的疗效，并证明输注镁可导致脊髓血流增加。该研究分两部分进行。首先，使用具有两种不同缺血时间（10分钟和14分钟）的大鼠模型评估镁的神经保护作用。通过阻断降主动脉诱导脊髓缺血。治疗组大鼠在缺血前给予100mg/kg硫酸镁输注。其次，使用激光多普勒血流仪技术记录缺血前后脊髓血流的相对变化。比较镁组和对照组之间的血流变化。在10分钟（截瘫发生率：对照组62.5% vs. 镁组37.5%，每组n = 8）和14分钟（对照组85.7% vs. 镁组57.1%，每组n = 7）的缺血后，预先用镁处理的大鼠总体恢复良好，尽管与对照组相比差异无统计学意义。然而，镁组在缺血后早期的神经功能表现明显更好。脊髓循环变化的比较显示，镁治疗组在缺血期间血流减少较少。总之，镁可能通过扩张脊髓血管系统发挥神经保护作用，在缺血期间具有潜在的预防益处。据我们所知，这种对脊髓的血管舒张作用此前尚未被研究过。然而，需要优化治疗方案。
