甲基强的松龙对脊髓损伤影响的组织学观察
作者：雷文海，谭军，谢幼专，曾明。
摘要：目的 探讨甲基强的松龙对医源性脊髓压迫损伤的影响。方法 取SD大鼠27只，随机分为实验组、对照组、空白组三组。实验组和对照组分别于术前和术后3 h给予甲基强的松龙剂量30 mg/kg静脉推注。维持剂量5.4 mg/(kg・h)。空白组术前3 h给予相同剂量的生理盐水。以25 g・cm致伤量直接打击脊髓致不完全损伤。分别于术后8 h、16 h、24 h，光镜观察受打击部位组织学变化。结果 使用甲基强的松龙较不使用损伤反应轻。打击前使用甲基强的松龙处理组损伤较打击后激素处理组轻。结论 术前使用甲基强的松龙对脊髓有明显保护作用。可明显减轻医源性脊髓压迫损伤带来的继发损害。
Histologic Changes of the Effects of Methylprednisolone(MP) on Pressural Injury of Spinal Cord Occurred During a Surgical Operation。
Abstract： Objective To investigate the effects of methylprednisolone(MP)on pressural injury of spinal cord occurred during a surgical operation. Methods Twentyseven SD rats were randomly divided into three groups. Rats in the experimental group were given with MP at a dose of 30 mg/kg intravenously 3 hours before operation and were given with a maintenance dosage of 5.4 mg/kg・h while in the control group， MP was injected into rats 3 hours after operation with the same dosage and same mode as the experimental group. In the blank group，rats were treated with physiological saline. Incomplete injuries were caused by direct striking against spinal cord with a magnitude of 25 g・cm， Histologic changes of the damaged spinal cord were observed under light microscope on the 8th， 16th， 24th hour respectively after striking. Results Histologic changes of the damaged spinal cord in the rats treated with MP were found to be much less than those in the blank group， and similar results were found in rats of the experimental group compared with those in the control group. Conclusion MP could protect the spinal cord from damages occurred during surgical operations and the effects could be enhanced by a dosage of MP using before operation.
Key words： methylprednisolone； spinal cord pressural injury； histology。
脊髓压迫和损伤是严重危害人类健康的疾病，虽然进行大量研究，发现其治疗前景较悲观。脊髓损伤一旦发生，尤其是完全损伤，其恢复十分困难。因此普遍认为预防比治疗更重要。近年来对甲基强的松龙在脊髓压迫和损伤的治疗上作了较多研究，发现其对脊髓压迫和损伤的恢复有一定作用。该实验是通过组织学观察证明术前预防性使用甲基强的松龙对减轻脊髓压迫和损伤是有效和有益的。
1 资料与方法。
1.1 实验分组 取SD大鼠27只，体重200～250 g，分三组，每组9只。实验组，术前3 h给予甲基强的松龙。给药方法：鼠尾静脉推注，冲击剂量30 mg/kg，维持剂量5.4 mg/(kg・h)。对照组，术后3 h给予甲基强的松龙。给药方法：鼠尾静脉推注，剂量30 mg/kg，维持剂量5.4 mg/(kg・h)。空白组，术前3 h给予生理盐水。给药方法：鼠尾静脉推注，剂量30 mg/kg，维持剂量5.4 mg/(kg・h)。
1.2 模型制备 取俯卧位，予氯胺酮40 mg/kg，腹腔内麻醉，行T12～L1椎板全切除术，之后以25 g・cm致伤量直接打击脊髓致不完全损伤。分别于术后8 h、16 h、24 h各处死每组3只大鼠，取受打击部位脊髓做标本。多聚甲醛固定，石蜡切片，HE染色。
1.3 光镜观察 分别观察上述三组动物受打击部位脊髓8 h、16 h、24 h后的组织学情况。
2 结 果。
2.1 实验组(打击前激素处理组) 在损伤后8 h，脊膜下出血少、有水肿表现；未见到充血、淤血及中央管周围出血坏死；在损伤后16 h，脊髓组织结构较清晰，脊髓灰、白质轻微水肿；可见到充血、淤血。在损伤后24 h，损伤部位可见呈片状出血及中央管周围出血坏死，神经元空泡变性轻，细胞核无明显固缩，神经细胞结构基本完整，细胞呈多角形，神经纤维极性完整。周边反应范围较小。分界清楚。