The Role of Histaminergic H2 Receptors on Spasmolytic Activity of Hydroalcoholic Extract of Parsley ( Petroselinum crispum ) Seeds in Isolated Rat’s Ileum

Objective: The long traditional history of anti-spasmodic effects of Petroselinum Crispum on the gastrointestinal system, and considering histamine receptors in rats ileum, to elucidate the role of the histamine receptor in function relate intestinal motility in this study investigate the effects of histamine and antagonists H2 receptor (Cimetidine) on contractions of adult male rat’s ileum. Methods: In this study, 2 cm of terminal isolated adult male rat’s ileum in an organ bath containing the oxygenated Tyrode solution (370c, PH = 7.4) was used and placed under 1 gram tension contraction induced by 60mM potassium chloride. The effect of parsley extract was measured in presence of histamine and antagonists H2 receptor (cimetidine) and their effects on the rat،s ileum contractions were recorded by using Harvard oscillograph. Results: The parsley extract reduced ileum contraction induced by KCl in a dose-dependent manner (P<0.001, n = 7). Spasmolytic effect of extract after tissue exposure to histamine (0.1 mg/ml) as an agonist and cimetidine (0.004 mg/ml) did not decrease ileum contractions. Conclusion: Although Parsley seeds extract reduced rat ileum contraction, it seems that H2 histamine receptors (cimetidine) are not involved in this activity.