Iranian Journal of Otorhinolaryngology

Iranian Journal of Otorhinolaryngology

Potential Histological Benefits of Gabapentin in Experimental Facial Nerve Crush Injury in Rats: Increased Myelinated Axons and S100-Positive Schwann Cells

Articles in Press

Document Type : Original

Authors
Farzaneh Fagheei 1
Maliheh Jahromi 2
Mohammad Javad Saeedi Borujeni 3
1 School of Dentistry, Student Research Committee, Isf.C., Islamic Azad University, Isfahan, Iran.
2 Clinical Development Research Center , Na.C., Islamic Azad University, Najafabad, Iran.
3 Department of Medical Basic Sciences, School of Dentistry, Isf.C, Islamic Azad University, Isfahan, Iran. Community Health Research Center, Isf.C, Islamic Azad University, Isfahan, Iran.
10.22038/ijorl.2026.96859.4182
Abstract
Introduction:
Some studies have shown that gabapentin administration is associated with neuroregeneration. The current study aimed to investigate the effects of daily gabapentin administration on the histological alterations of the facial nerve (FN) following experimental crush injury in Wistar rats.

Materials and Methods:
Twenty-one Wistar rats were randomly divided into three groups of seven: a sham-control group, a vehicle group, and a gabapentin group that received gabapentin after nerve injury induction. At the end of the intervention, the animals were sacrificed under anesthesia, and FN tissue samples were collected to evaluate the number of myelinated axons and Schwann cells. The data were analyzed using SPSS software, and a P value of less than 0.05 was considered statistically significant.

Results:
The mean number of myelinated axons was 37.00 ± 2.65 in the sham-control group, 19.86 ± 2.85 in the vehicle group, and 27.29 ± 2.93 in the gabapentin group, with the latter showing an intermediate value between the other two groups (η² = 0.879; P < 0.001). Similarly, the highest mean Schwann cell count was observed in the sham-control group (43.00 ± 2.89), whereas the lowest was found in the vehicle group (21.72 ± 2.06). The mean Schwann cell count in the gabapentin group was 34.29 ± 2.87 (η² = 0.928; P < 0.001).

Conclusion:
Daily gabapentin administration following FN crush injury resulted in a considerable increase in myelinated axons and S100-positive Schwann cells. These findings suggest that gabapentin may support structural nerve repair after FN injury. Further functional evaluation and cellular and molecular studies are needed.
Keywords
Gabapentin
Facial Nerve
Neuroregeneration
Subjects
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Iranian Journal of Otorhinolaryngology

Articles in Press, Corrected Proof
Available Online from 26 August 2026