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.μμthe role of β-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 β-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.