title: Effect of gabapentin and lamotrigine on mechanical allodynia-like behaviour in a rat model of trigeminal neuropathic pain.
abstract: Injury to the trigeminal nervous system may induce severe pain states. This study examined the antinociceptive effect of the novel anticonvulsants, gabapentin and lamotrigine, in a rat model of trigeminal neuropathic pain produced by chronic constriction of one infraorbital nerve. Responsiveness to von Frey filament stimulation of the vibrissal pad was evaluated 2 weeks post-operation. Hyper-responsive rats received acute and repeated (five injections separated by the half-life of the compound) injections with gabapentin and lamotrigine. 76% of the nerve-injured rats displayed pronounced hyper-responsiveness (median 0.217 g (lower-upper percentiles 0.217-0.217) vs. 12.5 g pre-operative), that was resistant to both single (5-100 mg/kg) and repeated (5-30 mg/kg) injections with i.p. lamotrigine. Repeated (30 and 50 mg/kg), but not single (30-100 mg/kg) injections of i.p. gabapentin partially alleviated the mechanical allodynia-like behaviour. Repeated injections of gabapentin at 50 but not at 30 mg/kg produced motor deficits. The results indicate that gabapentin rather than lamotrigine may be a better therapeutic approach for the clinical management of some trigeminal neuropathic pain disorders.
authors: Unité de Recherches de Physiopharmacologie du Système Nerveux, INSERM U-161, 2 rue d'Alésia, 75014 Paris, France.
authors: Dennis
authors: D
authors: Christensen
authors: Michèle
authors: M
authors: Gautron
authors: Gisèle
authors: G
authors: Guilbaud
authors: Valérie
authors: V
authors: Kayser
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D000588:Amines; D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003509:Cyclohexanecarboxylic Acids; D004195:Disease Models, Animal; D000077206:Gabapentin; D000077213:Lamotrigine; D008026:Ligation; D008297:Male; D009619:Nociceptors / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D014227:Triazines / Q000494:pharmacology*; D014277:Trigeminal Neuralgia / Q000188:drug therapy*; D005680:gamma-Aminobutyric Acid
chemical_list: D000085:Acetates; D000588:Amines; D000700:Analgesics; D003509:Cyclohexanecarboxylic Acids; D014227:Triazines; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin; D000077213:Lamotrigine