RESUMO
The antinociceptive and anti-inflammatory activities of crude ethanolic extract of Celtis iguanaea leaves and their active fractions are reported. The oral treatment with crude ethanolic extract (CEE; 100, 300 or 1000 mg/Kg) inhibited the number of writhings in a dose-dependent manner. The intermediate dose also inhibited formalin-induced nociception in both phases. The oral treatment with dichloromethane fraction (DF; 9 mg/Kg) produced antinociceptive effect in both phases of formalin test; however, the treatment with ethyl acetate fraction (EAF; 16 mg/Kg) reduced pain only in the second phase of this test. The oral treatments with CEE (300 mg/Kg) or DF (9 mg/Kg) reduced the nociception induced by capsaicin and pre-treatment with naloxone did not change these effects. The oral administration of CEE (300 mg/Kg), DF (9 mg/Kg) or ethyl EAF (16 mg/Kg) reduced ear edema, leukocytes migration and myeloperoxidase activity. Furthermore, the oral treatment with CEE (300 mg/Kg) or EAF (16 mg/Kg) reduced the level of Tumor Necrosis Factor - Alpha (TNF-α) in the pleurisy test. In conclusion, the DF showed antinociceptive activity that involves the vanilloid system as well as anti-inflammatory effect and the EAF showed anti-inflammatory activity involving the reduction of TNF-α cytokine.