大鼠T_7脊髓半横切损伤模型的建立及饲养护理

Establishment and nursing of Hemi-sect Spinal Cord Injury of T_7 segment model in rats

目的制备SD大鼠T7脊髓半横切动物模型，模拟脊髓损伤，为后期治疗脊髓损伤研究提供实验数据。方法24只健康SD大鼠随机分为对照组及脊髓损伤组，每组12只。SCI组咬除T6～8棘突及相应椎板，暴露相应脊髓，定量切除T7右半侧脊髓组织；对照组仅切除相应椎板。术后行人工排尿、排便等护理，于3d、7d分别进行BBB运动功能评分及感觉诱发电位（sensory evoked potentials，SEP）检测，并取T7脊髓行组织学观察。结果SCI组所有动物在术后均表现出典型的脊髓半切症状；BBB运动功能评分低于8分；术后3d及7d损伤组检测不到SEP，而对照组潜伏期轻度延长及波幅轻度下降；脊髓形态学观察显示该方法达到脊髓半横切要求；术后SCI组大鼠无死亡。结论大鼠T7脊髓半横切损伤模型建立成功，有效的术后护理可提高模型大鼠的生存率。

Objective To establish the right T7 spinal cord injury hemisection model in rats and provide reliable data for further therapy of spinal cord injury （SCI）. Methods Twenty-four healthy SD rats were randomly divided into two groups： control group and SCI group, each group had twelve rats. In SCI group： after the T6-8 spinous process and lamina were removed, the right half of T7 spinal cord was cut and a 0.5 cm long segment were removed to establish thorasic spinal cord hemisection model. In control group： only T6-8 lamina were removed. The locomotor functional recovery of hindlimbs was evaluated by grading BBB scale and SEP in three and seven days after operation. Then the T7 segment was cut for histomorphologial observation. Postop nursing measures were peformed in SCI rats. Results The rats in SCI group had the typical symptoms of paraplegina after hemisection and the BBB scales were significantly lower than that in control group, The latentperiod and amplitude of SEP in control group slightly changed after surgery, while no SEP was monitored in SCI group. The histomorphologial observation showed that this method meets the criterier of hemisection. No animal death were found in SCI group. Conclusion The right T7 spinal cord hemisection model in rats is successfully established and postop nursing measures can greatly increase the survival rate of spinal cord injury animals.