灯盏花素治疗大鼠继发性脊髓损伤的实验研究

Experimental study of breviscapine in treating secondary spinal cord injury in rats

目的探讨灯盏花素对大鼠脊髓损伤的保护作用及其机制。方法46只SD大鼠以改良Allen法制备中度脊髓损伤模型，按随机数字表法均分为实验组和对照组（各23只），造模后30min实验组大鼠腹腔注射灯盏花素6mg／kg，对照组注射等体积生理盐水，每天1次，共14d。损伤后8h、1d、2d、3d、4d采用硫代巴比妥酸（TBA）法、黄嘌呤氧化法分别测定大鼠脊髓中丙二醛（MDA）、超氧化物歧化酶（SOD）水平，伤后第2、4、6周末采用原位末端脱氧核糖核苷酸转移酶介导dUTP标记（TUNEL）法检测大鼠脊髓神经细胞凋亡指数及肢体运动功能（BBB法）评分。结果与对照组比较，实验组大鼠伤后8h、1d、2d、3d、4d脊髓组织SOD水平较高、MDA含量较低，伤后第2、4、6周末后BBB评分较高，神经细胞凋亡指数（伤后4周对照组、实验组分别为18．8％±3．1％、25．7％±3．2％）较低，差异均有统计学意义（P＜0．05）。结论脊髓损伤大鼠早期应用灯盏花素能改善微循环、有效清除自由基、减轻脂质过氧化反应和细胞凋亡，对损伤脊髓有保护作用。

Objective To explore the protective effect ofbreviscapine on rats with acute spinal cord injury （ASCI） and its mechanism. Methods Forty-six adult SD rats were used to establish the moderate spinal cord injury models at the T9 segment with modified Allen＇s method, and equally divided into 2 groups （n=23） randomly. The rats in the experimental group were given breviscapine 6 mg/kg per day for 14 d by intraperitoneal injection, while the rats in the control group were given normal saline of same volume. The concentration of malondialdehyde （MDA） and activity of superoxide dismutase （SOD） of the injured spinal cord tissues were measured with thiobarbituric acid （TBA） method and Xanthine oxidase method, respectively, 8 h, and 1, 2, 3 and 4 d after the injury; cell apoptosis index in the spinal cord was observed by terminal deoxyribonucleotide transferase-mediated dUTP labeling （TUNEL） at the end of 2, 4 and 6 weeks of injury; and the changes ofhindlimbs locomotor function was assessed using Basso-Beattie-Bresnahan （BBB） scale. Results As compared with those in the control group, the SOD activity and the BBB scale scores in the experimental group were significantly increased （P〈0.05）, and the concentration of MDA and the apoptotic index （18.8%±3.1% and 25.7%±3.2%, respectively） in the spinal cord of experimental group were decreased markedly at each observation time point （P〈0.05）. Conclusions Breviscapine could protect the spinal cord from secondary lesion by alleviating the impaired microcirculation damage and lipid peroxidation, inhibiting the production of free radicals and cell apoptosis at early stage of ASCI. Meanwhile, Breviscapine could promote the recovery speed and final recovery degree of locomotor fimction in rats.