Effect of Riluzole on Spinal Cord Regeneration with Hemisection Method Before Injury.

Objective: The pathophysiology of spinal cord injury (SCI) with the information obtained to date has not been elucidated fully. A safe drug or treatment protocol that results in cell regeneration for SCI remains unknown. Neuroprotective and neuroregenerative effects of riluzole, administered after a SCI, have been shown in experimental studies. This study aimed to investigate the effect of riluzole on neural regeneration in a rat SCI model.

Methods: Thirty-two rats were divided into 8 groups, with 4 rats in each group. Hemisection method was performed after T7-T9 laminectomy. Rats were intraperitoneally aministered with riluzole (6 mg/kg). Locomotor recovery of the rats was assessed at 1 day, and 1, 2, 3, and 4 weeks after the 21-point Basso, Beattie, and Bresnahan test. Subsequently, the spinal cords of the rats were scored according to a semiquantitative grading system using a light microscope, and the numbers of myelinated axons, neurons, and glial cells were calculated.

Results: Basso, Beattie, and Bresnahan test changes were statistically significant when groups 4-6 and 8 were compared with the other groups (P < 0.05, P < 0.00625). The results of the numbers of neurons, glial cells, and myelinated axons were statistically significant. Especially group 8, in which riluzole was administered 5 days before injury, more positive clinical and histopathologic results were obtained.

Conclusions: Riluzole treatment is more effective when provided before injury. Riluzole may contribute to functional recovery when used in the preoperative period in patients who are at a high risk for permanent neurologic deficit.