Background: Due to the harmful side effects of chemical drugs, in recent decades, much attention has been returned to the use of medicinal plants. The flavonoids as plant secondary compounds are allocated to own an important part of this attention. Based on previous studies, some of the flavonoids are able to reduce contraction induced by KCl, acetylcholine, etc in rat ileum. Therefore, in this study, the effect of the flavonoid extract of parsley leaves on smooth muscle contraction of the ileum and the role of Nitric oxide (NO) has been studied.

  Materials and Methods: Distal segment of Wistar rat ileum was separated and contractions under one gram tension and at 37°C, in an organ bath containing Tyrode solution was recorded by isotonic method. Rats were divided into 2 groups with 7 in each group. After placing the tissue exposed to L-NAME 100&muM (Sigma, America) as an inhibitor of NO, the antispasmodic effect of cumulative concentrations of the flavonoid extract was investigated

  Results: The extract cumulative concentrations reduced ileum contraction induced by KCl in a dose-dependent manner. Also, the antispasmoide effect of flavonoids extract on ileum contractions (only 16 mg/ml) was affected by L-NAME.

Conclusion: This study showed that the extract relaxed rat's ileum by the NO system at higher concentrations.

Background: because of the side effects of chemical drugs, using plant drugs was considered during recent decades. Based on previous studies, various concentrations of plant extracts can reduce ileum contraction caused by KCl and carbachol. Therefore, in this study, the role of muscarinic receptors in anti-spasmolytic activity of hydroalcohlic extract of parsley(petroselinum crispum)seed in adult male rat's ileum was investigated.

Materials and Methods: The distal part of Wistar rat’s ileum was separated and its contractions were recorded under 1 gr stretching and 37^oC temperature in the bathroom containing the solution of Tyrode by Isotonic method. The ileum tissue was inserted in separately in first group affected by KCl and parsley seed, in the second group affected by KCl and carbachol with concentration 10^-2 mg/ml and after that parsley seed, the third group affected by carbachol with concentration 10^-2 mg/ml and then the extraction of parsley seed and the fourth group affected by scopolamine with concentration 10^-3 M and after that KCl and then the extraction of parsley seed.

Results: Non-cumulative concentrations of extract reduced the ileum contraction caused by KCl (60mM) in a concentration-dependent form (p<0.001). There was a significant difference between the effect of extract in the presence of carbachol and extract concentration 0.2 mg/ml (p<0.01). There was no significant difference between the effect of extract in the presence of carbachol without stimulating tissue by KCl (60mM) with extract concentration 0.2mg/ml (p<0.05). There was no significant difference between the effect of extract in the presence of scopolamine with extract concentration 0.2mg/ml(p<0.05).

Conclusion: This study showed that the hydroalcholic of parsley seed extract has a relaxatory effect on rat’s ileum. Carbachol with KCl has a synergistic effect on smooth muscle contraction of the ileum wall and muscarinic receptors do not involve in the inhibitory function of parsley seed extract.

Abstract

Background: Parsley is one of the medicinal herbs used for gastrointestinal disorders. However, spasmolytic activity of Petroselinum crispum (parsley) extract has been reported, there is a lack of information to support the mechanism of this antispasmodic activity. Taking this into account, the purpose of the present work was to investigate the role of GABA_A receptor on antispasmodic activity of the hydroalcoholic extract of parsley seed in isolated rat ileum.

Materials and Methods: In this study, terminal portion of ileum (2 cm) was dissected out and mounted in an organ bath containing air bubbled Tyrode solution (37^οC, pH=7.4). Under 1gr resting tension, ileal contraction was induced by KCl (60 mM) and recorded isotonically. The effects of non-cumulative (0.1-0.5 mg/ml) concentrations of extract on KCl-induced contractions were examined.  After evaluating the effect of agonist and antagonist GABA_A receptor, the effect of parsley extract was assessed in the presence of muscimol (25 µM) and bicuculline (10 µM) as agonist and antagonist of GABA_A, respectively. 

Results: Parsley seed extract reduced the KCl-induced ileal contraction in a concentration-dependent manner (n=7, p<0.001). Both muscimol and bicuculline exerted relaxant effect on ileal contraction (n=7, p<0.05, p<0.01, respectively). Surprisingly, agonist and antagonist of GABA_A both potentiated the spasmolytic effect of extract (0.2 mg/ml). Altogether, spasmolytic effect of extract was not attenuated in the presence of GABA_A antagonist.

Conclusion: It seems that GABA_A receptor is not involved in the antispasmodic effect of parsley seeds extract in rat ileum.