Pregabalin and Gabapentin's Roles in Nerve Regeneration: Multifaceted Analysis in an Experimental Model

AIM: To compare the effects of pregabalin and gabapentin on the regeneration of rat nerves exposed to experimental axonotmesis by means of histomorphological, immunohistochemical, biochemical, electrophysiological, and clinical evaluations. MATERIAL and METHODS: Thirty-two female Sprague-Dawley rats were divided into four groups of eight animals each; Group 1 (control), Group 2 (axonotmesis + normal saline), Group 3 (axonotmesis + pregabalin 30 mg/kg), and Group 4 (axonotmesis + gabapentin 30 mg/kg). Medical treatment was given for the first seven days to groups 3 and 4. Functional recovery was assessed using electromyography (EMG) and the sciatic functional index (SFI). Sciatic nerves were excised for histomorphological, immunofluorescence, and immunohistochemical examinations. Biomarkers were measured using the enzyme-linked immunosorbent assay method. RESULTS: Significant improvement in SFI scores and EMG measurements were observed on the 28th day in groups 3 and 4 (the treated groups), while Group 2 (untreated) exhibited inadequate recovery. Histomorphological and immunohistochemical analyses revealed notable decreases in Wallerian degeneration, necrosis, inflammation, and nuclear factor-kappa B (NF-kappa B) expression levels in the treated groups compared to Group 2. The groups receiving medical treatment exhibited increased staining areas for nerve growth factor (NGF). Biochemical assessment indicated elevated levels of NGF, ciliary neurotrophic factor, transforming growth factor beta, and myelin basic protein in the treated groups compared to Group 2. CONCLUSION: Overall, the study findings suggest that both pregabalin and gabapentin exert neuroprotective effects and can contribute to the regeneration process, with no apparent superiority of one over the other.