Effects of repetitive magnetic stimulation on motor function and GAP43 and 5-HT expression in rats with spinal cord injury

OBJECTIVES: Spinal cord injury (SCI) is a disabling central nervous system disorder. This study aimed to explore the effects of repetitive trans-spinal magnetic stimulation (rTSMS) of different spinal cord segments on movement function and growth-associated protein-43 (GAP43) and 5-hydroxytryptamine (5-HT) expression in rats after acute SCI and to preliminarily discuss the optimal rTSMS treatment site to provide a theoretical foundation and experimental evidence for clinical application of rTSMS in SCI. METHODS: A rat T10 laminectomy SCI model produced by transient application of an aneurysm clip was used in the study. The rats were divided into group A (sham surgery), group B (acute SCI without stimulation), group C (T6 segment stimulation), group D (T10 segment stimulation), and group E (L2 segment stimulation). RESULTS: In vivo magnetic stimulation protected motor function, alleviated myelin sheath damage, decreased NgR and Nogo-A expression levels, increased GAP43 and 5-HT expression levels, and inhibited terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells and apoptosis-related protein expression in rats at 8 weeks after the surgery. CONCLUSIONS: This study suggests that rTSMS can promote GAP43 and 5-HT expression and axonal regeneration in the spinal cord, which is beneficial to motor function recovery after acute SCI.