脊髓缺血损伤动物模型的建立

The Establishment of Porcine Model of Spinal Cord Ischemic Injury

目的本研究拟建立胸降主动脉手术脊髓缺血动物模型,为脊髓保护策略和药物干预研究提供基础。方法实验中采用6只北京农大小型猪。经左侧第五肋间开胸,常温条件下在锁骨下动脉以远阻断降主动脉,30m in后阻断开放。动物复苏后,对其下肢行为学临床评分每日进行观察。7日后处死动物取材,进行损伤区域脊髓超微结构观察。结果术中血液动力学平稳。血气结果均维持在正常范围。复苏后1只动物术后每天肌力均为IV级,7天后处死时肌力IV^V级;其余5只动物术后下肢肌力0~I级。电子显微镜超微结构观察显示脊髓较严重的损伤性改变。结论应用小型猪为动物模型,在常温条件下胸降主动脉阻断30m in,可以建立急性脊髓缺血术后截瘫模型。

OBJECTIVE This study was designed to establish a porcine model of spinal cord ischemic injury produced by descending thoracic aorta occlusion and provide basis for strategy of spinal protection and pharmaceutical intervention. METHODS Six piglets were used in the experiments supplied by the Beijing College of Agriculture. A standard left thoracotomy was made through the fifth intercostal＇s space. The descending aorta was clamped distal to left subclavian artery at normothermia. Thirty minutes later, the clamps were released. The trachea was extubated once the animals recovered breathing spontaneously. The animals were evaluated daily according to a quantitative behavioral score. On postoperative seventh day the animals were sacrificed and histological analysis for the injury of spinal cord was made. RESULTS Hemodynamic data showed all animals were stable before, during and after the procedure. The results of behavioral scoring for each animal demonstrated one animal with paraparesis and other 5 animals with paraplegia. The injury of spinal cord was also demonstrated by ultrastructural measurement. CONCLUSION A porcine model of spinal cord isehemic injury can be established by descending thoracic aortic clamping thirty minutes at normothermia.