Effect of lafutidine on inflammatory pain

Abstract

We investigated the effect of lafutidine on inflammatory pain. This was done by studying how capsaicin receptors (TRPV 1) affected lafutidine by pretreating animals with a capsaicin antagonist, capsazepine. We prepared an inflammatory pain model, the complete Freund's adjuvant (CFA) model, and investigated the development of inflammatory pain using behavioral assessments. Lafutidine was administered to the hind paw of experimental rats at 10 and 150mg/kg, and the effect was investigated using behavioral assessments. We found that although heat-hyperalgesia and mechano-allodynia induced by inflammation were slightly promoted at 10mg/kg, hypoalgesia and hypoesthesia were noted at 150mg/kg. The latter findings were not seen at 10mg/kg. Pretreatment with capsazepine inhibited these effects. We concluded that lafutidine exhibited different actions on inflammatory pain depending on the dose, and that the effects were exhibited through capsaicin-sensitive sensory nerves. Based on these findings, we concluded that TRPV 1 is closely involved in the pain mechanism, and that lafutidine may be effective for painful disorders.