INHIBITORY EFFECTS OF THE AQUEOUS EXTRACT OF PAVETTA CRASSIPES LEAVESON GASTROINTESTINAL AND UTERINE SMOOTH-MUSCLE PREPARATIONS ISOLATED FROM RABBITS, GUINEA-PIGS AND RATS

The effects of the aqueous extract of Pavetta crassipes leaves were st udied on gastrointestinal and uterine smooth muscle preparations isola ted from rabbit jejunum, guinea pig ileum and rat uterus. The extract produced a concentration-dependent inhibition of the spontaneous motil ity or elevated tone in these preparations. The inhibitory effects of the extract were not affected by pretreatment with propranolol or yohi mbine, but were completely blocked by verapamil pretreatment. The resu lts indicate the presence of biologically active substances whose acti on might be mediated through calcium channels. A preliminary phytochem ical screening of the leaf extract of P. crassipes revealed the presen ce of flavonoids, tannins and anthraquinones as possible candidates fo r such inhibitory substances. (C) 1998 Elsevier Science ireland Ltd. A ll rights reserved.