New protopine alkaloids from Aristolochia constricta reduce morphine withdrawal in vitro

The present study examines the effect of four new protopine alkaloids (1-4) isolated and purified from the aerial parts of Aristolochia constricta (Ar istolichiaceae) on morphine withdrawl in vitro. The results of our experime nts indicate that the pure compounds (1-4) significantly and in a concentra tion-dependent manner reduced the morphine withdrawal. The results of the p resent study suggest that these new protopine alkaloids may be potential an ti-addictive agents. Copyright (C) 2000 John Wiley & Sons, Ltd.