Influence of some traditional medicinal plants of Senegal on prostaglandin biosynthesis.

Aqueous extracts of Combretum micranthum G. Don, Euphorbia hirta L., Guiera senegalensis Lam. and Melaleuca leucadendron L. were investigated for their influence on prostaglandin biosynthesis (PG I2, PG E2, PG D2). Only the extract of Euphorbia hirta strongly reduced the release of prostaglandins I2, E2, and D2. Additionally Euphorbia hirta extracts exerted an inhibitory effect on platelet aggregation and depressed the formation of carrageenin induced rat paw oedema. The chemical nature of the active principle of Euphorbia hirta could be characterized as (a) compound(s) of medium polarity in the molecular weight range of 1000 to 3000 Da.