ANALGESIC AND ANTIPYRETIC ACTIVITIES OF AN AQUEOUS EXTRACT AND OF THEFLAVONE LINARIN OF BUDDLEIA-CORDATA

The dried aqueous extract of leaves of Buddleia cordata (Loganiaceae) and its main flavonoid glycoside, linarin, have been evaluated for ana lgesic and antipyretic effects in mice and rats, respectively. Both th e extract and linarin exerted significant and dose-dependent analgesic and antipyretic activities, the first being obtained against a chemic al stimulus (writhing test in mice) and the second being obtained by a pyretogenic stimulus (yeast-induced hyperthermia test). Furthermore, the response of the animals in the hot plate test was modified by lina rin and an aqueous extract. These activities were similar to that show ed by morphine sulfate (MS) and they were inhibited by naxolone pretre atment, a specific morphinic antagonist compound. These findings lead to the conclusion that the aqueous extract and linarin exert central a nalgesic properties. On the other hand, linarin was shown to be respon sible for the antipyretic activity of this species.