TY - JOUR T1 - Gabapentin Attenuates Nociceptive Behaviors in an Acute Arthritis Model in Rats JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 214 LP - 219 VL - 290 IS - 1 AU - Ying Lu AU - Karin N. Westlund Y1 - 1999/07/01 UR - http://jpet.aspetjournals.org/content/290/1/214.abstract N2 - In this study, we investigated the effectiveness of gabapentin (Neurontin), administered spinally with a microdialysis fiber, in reducing nociceptive behavioral responses induced by a knee joint inflammation model. This model is produced by injection of the knee joint with kaolin and carrageenan in rats. The resultant knee joint inflammation produces a secondary hyperalgesia to radiant heat applied to the hindpaw. Both pretreatment and post-treatment protocols were examined. Spinal administration of gabapentin (10 mg/ml) infused 1.5 h before induction of knee joint inflammation, although having no effect on the baseline, prevented the development of heat hyperalgesia. Gabapentin also prevented the development of other pain-related behaviors scored subjectively. Gabapentin had no effect, however, on the joint circumference increase typical in this model. In animals with fully developed knee joint inflammation, gabapentin produced a reversal of heat hyperalgesia. The paw withdrawal latency responses and subjective pain scores were no longer significantly different from baseline, but joint circumference increases remained. These data suggest that gabapentin is an effective antinociceptive agent when administered either before or after induction of knee joint inflammation acting through a central neurogenic mechanism. The American Society for Pharmacology and Experimental Therapeutics ER -