甲基强的松龙预防牵张性脊髓损伤的实验研究

EXPERIMENTAL STUDY ON THE EFFICACY OF METHYL PREDNISOLONE IN THE TREATMENT OF TRACTION INJURY OF SPINAL CORD IN RABBITS

为探索甲基强的松龙（ＭＰ）对牵张性脊髓损伤的防治作用，选用日本大耳白兔４８只，随机分为对照组（Ａ、Ｂ）、实验组（Ｃ、Ｄ）。实验组于伤前３０分钟一次静脉缓慢推注ＭＰ３０ｍｇ／ｋｇ；伤后１５分钟开始，每１小时静脉滴注ＭＰ５．４ｍｇ／ｋｇ，持续５小时。对照组用生理盐水治疗。采用皮质体感诱发电位（ＳＣＥＰ）监护、组织形态学、脊髓组织生化测定、运动功能评定等方法评价。结果表明，Ｃ组、Ｄ组较Ａ组、Ｂ组ＳＣＥＰＰ１波波幅恢复快速、稳定；伤后８小时及１４天运动功能评定其障碍率低于Ａ组、Ｂ组（Ｐ＜０．０５）；脊髓前角灰质神经元体积密度及１００μｍ白质范围内有髓神经纤维数高于Ａ组、Ｂ组（Ｐ＜０．０５）；丙二醛含量低于Ａ组、Ｂ组，过氧化物歧化酶含量高于Ａ组、Ｂ组（Ｐ＜０．０５）；神经元及神经纤维变性、坏死，灰质出血范围及脊髓微血管痉挛程度明显轻于Ａ组、Ｂ组。认为，在脊柱畸形矫正术前应用大剂量ＭＰ，具有预防牵张性脊髓损伤的作用；伤后及时给予ＭＰ。

In order to study the prophylactic and therapeutic effect of methyl-prednisolone (MP) on traction injury of spinal cord, 48 rabbits were divided into four groups randomly. According to decreasing amount of the amplitude of P1wave, 50% reduction lasted for 5 min and 10min with MP as experimental group, and 50% 5 min and 10 min with NS as control, the changes of amplitudes were monitored by, and the function of the spinal cord was assessed. The amounts of MDA and SOD of the spinal cord tissue were determined and the pathomorphological changes of the spinal cord were observed. The results showed that in the experimental groups, the recovery of P1wave was quicker, the Tarlov and Molt value were decreased, the density of gray matter of the anterior horn and the myelinated nerve fiber of white matter of 100 μm diameter were higher, the SOD and MDA was decreased and the degenerative and necrotic degree of neuron and nerve fiber were milder. Where in the control groups all the above items were just on the opposite. The conclusions list as follows: the application of MP before operation of spinal deformity might prevent traction injury of the spinal cord during operative correction of spinal deformity, and could also minimized the secondary damage to spinal cord from traction injury if MP was used in time. The action to MP were summarized as improving the microcirculation, inhibiting the hyperoxidation of lipid and accelerating the recovery of SCEP.