title: Gabapentin attenuates neuropathic pain and improves nerve myelination after chronic sciatic constriction in rats.
abstract: Gabapentin (GBP) is an anti-convulsive drug often used as analgesic to control neuropathic pain. This study aimed at evaluating oral GBP treatment (30, 60, 120 mg/kg, 60 min prior to chronic constriction of the sciatic nerve (CCSN) along 15-day treatment post-injury, 12 h/12 h) by monitoring spontaneous and induced-pain behaviors in Wistar rats on 5th and 15th days post-injury during early neuropathic events. CCSN animals receiving saline were used as controls. Another aim of this study was to evaluate GBP effects on myelin basic protein (MBP) on the 5th and 15th days post-injury and nerve morphology by transmission electron microscopy to address nerve regeneration. On the 5th and 15th days, GBP (60 mg/kg) reduced neuropathic pain behaviors (scratching and biting) in the ipsilateral paw and alleviated mechanical allodynia in comparison with the neuropathic saline group. GBP significantly increased climbing and rearing behaviors in CCSN and CCSN-free animals suggesting increased motor activity rather than sedation. We found three-fold significant increase in MBP expression by western blots on the 15th day when compared to controls. In addition, GPB (60 mg/kg) improved nerve axonal, fiber and myelin area 15 days post-surgery. In conclusion, GBP alleviated mechanical and thermal allodynia and spontaneous pain-related behaviors and improved later nerve morphology. Our findings suggest that GBP improve nerve remyelination after chronic constriction of the sciatic nerve.
authors.affiliation: Laboratory of Neurophysiology, Federal and Rural University of the SemiArid-UFERSA, Mossoro, RN, Brazil; Laboratory of Tissue healing, Ontogeny and Nutrition, Department of Morphology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Carlos C
authors.initials: CC
authors.lastname: Câmara
authors.affiliation: Laboratory of Tissue healing, Ontogeny and Nutrition, Department of Morphology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Celina V
authors.initials: CV
authors.lastname: Araújo
authors.affiliation: Laboratory of Tissue healing, Ontogeny and Nutrition, Department of Morphology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Kalina Kelma Oliveira
authors.initials: KKO
authors.lastname: de Sousa
authors.affiliation: Laboratory of Inflammation and Cancer, Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Gerly A C
authors.initials: GAC
authors.lastname: Brito
authors.affiliation: Laboratory of Inflammation and Cancer, Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Mariana L
authors.initials: ML
authors.lastname: Vale
authors.affiliation: Experimental Biology Core, University of Fortaleza, Fortaleza, CE, Brazil.
authors.forename: Ramon da Silva
authors.initials: RDS
authors.lastname: Raposo
authors.affiliation: Department of Pathology, Faculty of Medicine, HUCFF, Health Science Center, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Fabiana Evaristo
authors.initials: FE
authors.lastname: Mendonça
authors.affiliation: Department of Pathology, Faculty of Medicine, HUCFF, Health Science Center, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Bruno S
authors.initials: BS
authors.lastname: Mietto
authors.affiliation: Department of Pathology, Faculty of Medicine, HUCFF, Health Science Center, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Ana Maria B
authors.initials: AMB
authors.lastname: Martinez
authors.affiliation: Laboratory of Tissue healing, Ontogeny and Nutrition, Department of Morphology, Faculty of Medicine, Federal University of Ceara, Fortaleza, CE, Brazil. Electronic address: rbo5u@virginia.edu.
authors.forename: Reinaldo B
authors.initials: RB
authors.lastname: Oriá
mesh_terms: D000588:Amines / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology / Q000627:therapeutic use*; D003251:Constriction, Pathologic; D003509:Cyclohexanecarboxylic Acids / Q000494:pharmacology / Q000627:therapeutic use*; D000077206:Gabapentin; D008297:Male; D004676:Myelin Basic Protein / Q000378:metabolism*; D009416:Nerve Regeneration; D009437:Neuralgia / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000187:drug effects* / Q000293:injuries / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000588:Amines; D000927:Anticonvulsants; D003509:Cyclohexanecarboxylic Acids; D004676:Myelin Basic Protein; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin
keywords: Gabapentin; Nerve myelination; Neuropathic pain; Sciatic nerve