antispasmodic effects of citrus aurantium flowers aqueous extract on uterus of non-pregnant rats

background: citrus aurantium is a small citrus tree, with scented white flowers. the c. aurantium is used in asian herbal medicine primarily to treat digestive problems. objective: the goal of this study is to investigate the effect of c. aurantium flower's aqueous extract on uterine contraction in presence of some known uterus stimulants. materials and methods: in experimental study 30 virgin wistar rats 200-300gr were obtained. after laparatomy, a piece of uterus was dissected out and mounted in an organ bath (10ml) containing de jalon (29°c) and contracted by kcl (60mm), oxytocin (10mu/ml) and barium chloride (4mm) then the effect of c. aurantium flower's aqueous extract (1-8 mg/ml) on the uterine contractions was investigated. uterus was separately incubated with propranolol (1?m), naloxone (1?m) and the role of ?-adrenoceptors, opioid receptors were evaluated. results: cumulative concentrations of the extract (1-8 mg/ml) decreased kcl, oxytocin and barium chloride induced uterine contractions, dose-dependently (p<0.001). c. aurantium flower's aqueous extract was unaffected on incubation the tissue with propranolol and naloxone. conclusion: it seems that the extract induced antispasmodic effect mainly via calcium influx blockade. however, neither ?-adrenoceptors nor opioid receptors were involved. since the extract has antispasmodic effect on uterus contraction therefore we can suggest that more study will be necessary to relief dysmenorrheal