Evaluation of antinociceptive and antiinflammatory effects of Croton pullei var. glabrior Lanj. (Euphorbiaceae)

Abstract

Croton pullei var. glabrior Lanj. (Euphorbiaceae) is a liana, vastly distributed in the Amazonian Forest. In the folk medicine, several plants of the Croton genus have been used with therapeutic purposes in pathologies that involve painful and inflammatory diseases which justify this work. The aim of this study was to investigate the antinociceptive and antiinflammatory activities of the C. pullei leaves methanol extract (MECP). MECP reduced in a dose-dependent manner the number of acetic acid-induced abdominal writhing (1.2%) in mice, suggesting an antinociceptive activity of the plant. On the other hand, MECP did not significantly modify the reactivity to the thermal stimulation in the hot-plate test and the reactivity to the chemical stimulation in the formalin test first phase, indicating a non-opioid mechanism. MECP reduced the formalin-induced nociception in the second phase, inhibited the croton oil-induced ear edema and reduced the leukocytes migration in the test of the carrageenan-induced peritonitis, indicating an antiinflammatory activity. Although the mechanisms that underlie these plant effects are not completely elucidated, these results appear to support the potential medicinal use of Croton pullei var. glabrior Lanj. against painful and inflammatory diseases.