title: The neurological safety of epidural gabapentin in rats: a light microscopic examination.
abstract: Gabapentin acts primarily on the central nervous system. Therefore, we hypothesized that the direct epidural administration of gabapentin could have various advantages over its oral administration with respect to required dose, side effects, and efficacy. However, before administering gabapentin into the epidural space in a clinical setting, its neurotoxicity must be examined in animals. Thus, we evaluated neurotoxicity of epidural gabapentin by observing behavioral and sensory-motor changes, and by histopathological examinations of spinal cords and dorsal root ganglia in the rat. Twenty-seven rats were randomly divided into 3 groups, which were administered 0.3 mL (30 mg) of epidural gabapentin (group G, n = 9) and the same volume of epidural alcohol (group A, n = 9) or normal saline (group N, n = 9). No rats in groups G and N showed sensory-motor dysfunction, behavioral change, or histopathological abnormalities over a 3-wk observation period, whereas all rats in group A showed abnormalities. We conclude that the direct epidural injection of gabapentin in rats did not show any neurotoxic evidence in terms of sensory-motor functions and behavior, or by a microscopic histopathological evaluation. This study represents a first promising step toward the trial of epidural gabapentin in a clinical setting.
authors.affiliation: *Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine; and Departments of †Anesthesiology and Pain Medicine and ‡Diagnostic Pathology, SungKyunKwan University College of Medicine, Seoul, Korea.
authors.forename: Sang-Sik
authors.initials: SS
authors.lastname: Choi
authors.forename: Yong-Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Lim
authors.forename: Chul-Joong
authors.initials: CJ
authors.lastname: Lee
authors.forename: Pyung-Bok
authors.initials: PB
authors.lastname: Lee
authors.forename: Sang-Chul
authors.initials: SC
authors.lastname: Lee
authors.forename: Woo-Seok
authors.initials: WS
authors.lastname: Sim
authors.forename: Yoon-La
authors.initials: YL
authors.lastname: Choi
mesh_terms: D000588:Amines / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D003509:Cyclohexanecarboxylic Acids / Q000008:administration & dosage / Q000633:toxicity*; D000077206:Gabapentin; D005727:Ganglia, Spinal / Q000187:drug effects / Q000473:pathology; D007268:Injections, Epidural; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000187:drug effects* / Q000473:pathology; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000633:toxicity*
chemical_list: D000588:Amines; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin