Purpose Pregabalin exhibits potent anticonvulsant, analgesic, and anxiolytic activity in animal models. However, few studies have evaluated pregabalin's potential peripheral effects on neuropathic pain. The aim of this study was to evaluate the peripheral analgesic effects of pregabalin in a rat model of neuropathic pain. Methods Male Sprague-Dawley rats were prepared by ligating the left L5 and L6 spinal nerves to produce neuropathic pain. Sixty rats with neuropathic pain were randomly assigned to six groups. Normal saline (control) and pregabalin (10,20,30, and 50 mgÁkg -1 ) were administered to the plantar surface of the affected left hind paw. Pregabalin (50 mgÁkg -1 ) was administered into the unaffected contralateral paw in order to determine its systemic effect. Responses to mechanical, cold, and heat stimulation were recorded at 15,30, 60, 90, 120, 150, and 180 min after drug administration. Rotarod performance was measured to detect drug-induced side effects, including sedation and reduced motor coordination. Results Saline injected into the affected paw and a pregabalin dose of 50 mgÁkg -1 injected into the contralateral paw showed no differences for mechanical, cold, and heat allodynia. Administration of pregabalin to the affected left hind paw in the dose range of 10-50 mgÁkg -1 resulted in a dose-dependent increase in thresholds to mechanical, cold, and heat stimulation. Conclusion Peripherally administered pregabalin attenuates mechanical, cold, and heat allodynia in a rat model of neuropathic pain.
RésuméObjectif La pre´gabaline de´montre une puissante activiteá nticonvulsivante, analge´sique et anxiolytique dans les mode`les animaux. Ne´anmoins, il n'existe que peu d'e´tudes ayant e´value´les effets pe´riphe´riques potentiels de la pre´gabaline sur la douleur neuropathique. L'objectif de cette e´tude e´tait d'examiner les effets analge´siques pe´riphe´riques de la pre´gabaline dans un mode`le de douleur neuropathique chez le rat. Méthode Des rats Sprague-Dawley maˆles ont e´teṕ re´pare´s en ligaturant les nerfs rachidiens L5 et L6 afin de cre´er une douleur neuropathique. Soixante rats souffrant de douleur neuropathique ont e´te´ale´atoirement re´partis en six groupes. Du se´rum physiologique (te´moin) et de la pre´gabaline (10, 20, 30, et 50 mgÁkg -1 ) ont e´te´administre´s a`la surface plantaire de la patte arrie`re gauche affecte´e. De la pre´gabaline (50 mgÁkg -1 ) a e´te´administre´e à la patte controlate´rale non affecte´e afin de de´terminer son effet syste´mique. Les re´actions aux stimulations me´caniques, au froid et a`la chaleur ont e´te´enregistre´es a1 5, 30, 60, 90, 120, 150 et 180 min apre`s l'administration du me´dicament. La performance au test de la tige tournante a e´te´mesure´e afin de de´pister les effets secondaires provoque´s par le me´dicament, notamment la se´dation et une re´duction de la coordination motrice.This article is accompanied by an editorial. Please see Can J Anesth 2010; 57(7).