Evaluation of anti-inflammatory activity of some Swedish medicinal plants. Inhibition of prostaglandin biosynthesis and PAF-induced exocytosis.

Plants used in Swedish traditional medicine to treat inflammatory diseases and/or wounds were selected, based on literature data, for evaluation of inhibitory activity on prostaglandin biosynthesis and platelet activating factor (PAF)-induced exocytosis in vitro. Fifty-nine water extracts from 52 different plants in 28 families were tested. A number of plants, e.g. Calluna vulgaris, Corylus avellana, Geum urbanum, Juniperus communis, Polygonum aviculare, Potentilla erecta and Salix caprea were found to be active in both assays. The most potent cyclooxygenase inhibitors were extracts of Calluna vulgaris, Potentilla erecta and Salix caprea. None of the extracts inhibited just the prostaglandin biosynthesis. In the PAF-test, high inhibition was obtained by 19 extracts, the most potent of which were from Geum rivale, G. urbanum, Solanum dulcamara, Symphytum x uplandicum and Vaccinium vitis-idaea. The in vitro effects in relation to the traditional use, chemical contents and botanical classification, as well as the possibilities and the limitations of the methods are discussed.