Antinociceptive and antiinflammatory activities of Artemisia copa extracts

The aqueous extract from aerial parts of Artemisia copa Phil. (Compositae), was evaluated for antinociceptive activity using writhing, formalin, and hot-plate tests in mice. A dose-related antinociceptive response was obtained in the writhing test at doses of 500 and 1000 mg/kg p.o. (percentage of inhibition 23.3 and 52.70, respectively). The extract also inhibited the second phase of formalin test (38.81%) and this effect was not antagonized by pretreatment with naloxone 5 mg/kg i.p. Furthermore, no significant effect was obtained in the hot-plate test. Dichloromethane and ethanolic extracts, were analyzed for antiinflammatory activity with the carrageenan-induced paw edema in rats and the ear edema induced by 12-O-tetradecanoylphorbol-13 acetate (TPA) and arachidonic acid (AA) in mice. Both extracts showed antiinflammatory activity in the TPA (88 and 54%), and the ethanolic extract showed a 37% inhibition in AA test. No effects were seen at doses of 300 mg/kg p.o. and 100 mg/kg i.p. in the carrageenan test. The results obtained indicate that A. copa has analgesic and topical antiinflammatory activities that supports the folk medicinal use of the plant. (C) 2004 Elsevier Ltd. All rights reserved.