Background and purpose: Airway stenosis is one the most dangerous diseases. Anethum graveolens L.(Dill) has anti-spastic effect on smooth muscle. The aim of this study was to investigate the effect of the hydroalcoholic extract of this plant on male rat tracheal smooth muscle contractile activity.
Materials and methods: In this experimental study, tracheas of healthy rats were dissected. We investigated the effect of different concentrations of Dill hydroalcoholic extract in presence and absence of propranolol and L-NAME on reduction of tracheal smooth muscle contraction induced by potassium chloride.
Results: Compared with the negative and positive control groups, the extract of Anethum graveolens at 5 gr/l significantly decreased tracheal smooth muscle contraction induced by potassium chloride (P <0.05). Propranolol and L-NAME did not reduce the antispasmodic effect of Dill extract (P<0.05).
Conclusion: Hydroalcoholic extract of Anethum graveolens could inhibit the tracheal smooth muscle of rat contractions in a dose-dependent manner, but it seems that β-Adrenergic receptors and NO are not involved in this process.