兔爆炸性颅脑损伤模型的建立

Establishment of blast-related brain injury model in rabbits

目的建立一种稳定、可靠的颅脑爆炸伤动物模型。方法新西兰大白兔30只,按纸雷管与兔脑距离随机分成3组,每组10只。600mgTNT当量纸雷管垂直悬吊于兔脑上方爆炸,距离分别为5.0、6.5、8.0cm。观察动物伤后存活情况与生存质量,颅脑损伤区病理与MRI表现。结果5.0cm组兔伤后即刻死亡5只,3d内死亡4只,另1只存活7d以上。6.5cm组兔伤后发生癫疒间3只,肢体瘫痪1只,不能进食伤后4d死亡1只,余动物均存活7d以上;MRI示典型脑挫裂伤改变;病理示损伤区神经细胞变性坏死、空泡样变、周围水肿、微血管破裂出血;电镜观察示损伤区细胞超微结构破坏严重。8.0cm组动物均存活,但病理及MRI检查未见典型颅脑损伤改变。结论600mgTNT当量纸雷管在垂直兔脑上方6.5cm处爆炸,可造成稳定的颅脑爆炸伤模型。

Objective To establish a stable and reliable blast-related brain injury model in rabbits. Methods Thirty New Zealand white rabbits were randomly divided into three groups, 10 rabbits for each group： 5.0 cm group, 6.5 cm group and 8.0 cm group. Paper detonators with 600 mg TNT equivalent explosive were placed at the sites of 5.0 cm, 6.5 cm and 8.0 cm above the rabbit head respectively. The number of surviving rabbits, quality of life, pathology of brain damage and MRI manifestations were observed and recorded. Results Five rabbits died immediately after the injury, 4 rabbits died within 3 d, and the other one survived more than 7 d in 5.0 cm group. Epileptic seizures were observed in 3 rabbits and limb paralysis in 1 rabbit in 6.5 cm group. All rabbits survived more than 7 d except 1 rabbit who died because of inability to eat 4 d later in 6.5 cm group. All rabbits showed typical brain contusion by MRI in 6.5 cm group. Pathology analysis showed severe neuronal degeneration, necrosis and vacuolization, edema around nerve cells and capillary hemorrhage. Electron micrograph showed severe ultrastructural damage. All rabbits survived in 8.0 em group, but no significant pathological and MR/changes in injury area. Conclusions The explosion of a paper detonator with 600 mg TNT equivalent at a 6.5 cm place away-from the animal head can result in a stable and reliable brain injury animal model.