不同频率重复经颅磁刺激对脊髓损伤大鼠肌痉挛及运动功能的影响及机制研究

Effect and mechanism of repetitive transcranial magnetic stimulation at different frequencies on muscle spasm and motor function with spinal cord injury rats

目的:研究不同频次重复经颅磁刺(rTMS)对不完全性脊髓损伤(SCI)肌肉痉挛的作用及机制。方法:50只SD雌性大鼠随机分为正常对照组、模型组、1Hz组、5Hz组、10Hz组,每组10只。用Alleb’s方法将模型组及磁刺激组制作成不完全性脊髓损伤痉挛模型。磁刺激组于手术后2周开始给予刺激,频率分别为为1Hz、5Hz、10Hz,刺激强度为80%的RMT,磁刺激每天1次,连续4周,脊髓损伤模型组给予假刺激。各组大鼠干预前和磁刺激结束后观察其下肢BBB评分对大鼠后肢的运动功能进行评定、根据Ashworth评定对大鼠后肢的小腿三头肌痉挛程度进行评估、Western blot法检测脊髓损伤处GABA受体。结果:经过干预4周后BBB评分均有提高,磁刺激组与模型组比较差异均有统计学意义(P<0.05),以10Hz组最高最为明显,差异有显著意义(P<0.01);Ashworth评定,磁刺激组与模型组比较差异均有统计学意义(P<0.05),以10Hz组最高最为明显,差异有显著意义(P<0.01);Western blot法检测GABA受体,磁刺激组与模型组比较差异均有统计学意义(P<0.05),以10Hz组最高最为明显,差异有显著意义(P<0.01)。结论:rTMS可使SCI后大鼠的BBB和Ashworth、GABA受体指标变化较模型组改善明显,提示rTMS对不完全性脊髓损伤大鼠肢体痉挛有缓解作用,能够改善肢体功能,以10Hz频率最佳,值得临床推广应用。

Objective:To study the effect and mechanism of repetitive transcranial magnetic spine(rTMS) with different frequency on muscle spasm in incomplete spinal cord injury(SCI).Methods:Fifty SD female rats were randomly divided into normal control group,model group,1 Hz group,5 Hz group,and 10 Hz group,with 10 rats in each group.Using Alleb’s method,the model group and the magnetic stimulation group were made into incomplete spinal cord injury spasticity models.The magnetic stimulation group started to give stimulation 2 weeks after the operation,the frequency was 1 Hz,5 Hz,10 Hz,the stimulation intensity was 80% RMT,and the magnetic stimulation was once a day for 4 consecutive weeks.The spinal cord injury model group was given false stimulation.Observe the BBB(Basso,Beatti and Bresnahan,BBB) score of the lower limbs before operation and after the magnetic stimulation in each group of rats to evaluate the motor function of the hind limbs of the rats,and evaluate the spasm degree of the calf triceps of the hind limbs of the rats according to the Ashworth assessment.Evaluation,Western blot method to detect GABA receptors at spinal cord injury.Results:After 4 weeks of intervention,the BBB scores were improved,the magnetic stimulation group and the model group had statistically significant differences(P<0.05),with the 10 Hz group having the highest value,and the difference was significant(P<0.01);Ashworth Assessed,the difference between the magnetic stimulation group and the model group was statistically significant(P<0.05),with the 10 Hz group being the most significant,and the difference was significant(P<0.01);Western blot detection of GABA receptors,the magnetic stimulation group and the The differences between the model groups were statistically significant(P<0.05),with the 10 Hz group being the most obvious,and the differences were significant(P<0.01).Conclusion:rTMS can significantly improve the BBB,Ashworth,and GABA receptor indexes of rats after SCI compared to the model group,suggesting that rTMS can relieve limb spasm in rats with incomplete spinal cord injury and can improve limb function at a frequency of10 Hz.It is worthy of clinical application.