Anti-inflammatory activity of aqueous extracts of five Costa Rican medicinal plants in Sprague-Dawley rats

The anti-inflammatory properties of Loasa speciosa and Loasa triphylla (Loa saceae), Urtica leptuphylla and Urera baccifera (Urticaceae), and Chaptalia nutans (Asteraceae) were studied using the carregeenan induced rat paw ede ma model. Aqueous extracts of each plant were made according to the ethnobo tanical use. The hippocratic assay was made with female rats; the dose used was 500 mg/kg i.p. and the control group received 0.5 mi of n.s.s.. All th e animals treated showed hipothermia, and those treated with the extracts o f Chaptalia nutans, Urera baccifera and Urtica leptuphylla showed an increa sed colinergic activity. Acute toxicities of the aqueous extracts were stud ied in mice an the mean lethal doses ranged between 1.0226 and 1.2022 g/kg. The extracts of Urera baccifera, Chaptalia nutans, Loasa speciosa and Loas a triphylla (500 mg/kg i.p.) showed an antiinflammatory activity comparable with that of indomethacin. The extracts of U. baccifera and C. nutans, whi ch showed the greatest anti-inflammatory activity, did not show it when use d orally (500 mg/kg p.o.).