大剂量甲强龙冲击治疗大鼠脊髓挫伤的形态学研究

Studies on the morphology of spinal cord contusion rats treated by high-dose pulsed methylprednisolone

目的评价大鼠脊髓挫伤模型的稳定性及大剂量甲强龙冲击治疗的效果。方法采用BenchmarkTM颅脑撞击器建立大鼠脊髓挫伤模型。甲强龙组在伤后30 min尾静脉注射甲强龙(30 mg.kg-1BW)。运用Image J软件测量撞击区域的损伤体积。斜板试验评价动物后肢运动功能。采用Harris氏HE染色法结合尼氏染色、Luxol固蓝染色观察损伤组织的形态学改变。结果脊髓的平均损伤体积为(4.12±0.17)mm3,范围在3.95～4.29 mm3之间。甲强龙组随着训练天数的增加,大鼠在斜板上维持的角度逐渐增大,与模型组比较差异有显著性(P<0.05)。伤后28 d,脊髓损伤中心及邻近部位囊腔区域面积明显减小。伤后1、3 d,损伤中心灰质部神经元存活数量较多,与模型组比较差异有显著性(P<0.05)。伤后各个时间点,距损伤中心前后3、5 mm处灰质部前角神经元存活数量较多,与模型组比较差异有显著性(P<0.05)。伤后14、28 d,脊髓损伤中心及前后3 mm、5mm处髓鞘面积均高于模型组(P<0.05)。结论建立的控制性脊髓挫伤大鼠模型稳定性高。大剂量甲强龙冲击治疗可能通过保护神经元和髓鞘免受继发性损害而改善后肢运动功能。

Aim To evaluate the stability of spinal cord contusion model in rats and the neuroprotective effect of high-dose methylprednisolone（MP） pulse therapy.Methods Spinal cord contusion model in rats was duplicated by a BenchmarkTM stereotaxic cortical impactor.Posttraumatic 30 min,MP group was administrated by 30 mg.kg-1 BW MP through tail intravenous infusion.Image J software was used to measure the initial lesion volume of impact area.Morphological changes were inspected by using the Harris HE staining method combined with Luxol Fast Blue（LFB） staining and Nissl staining.The inclined plane test was used to assess the hindlimb motor function.Results The mean lesion volume of spinal cord was（4.12 ± 0.17）