title: Relaxant effect of Humulus lupulus extracts on isotonic rat's ileum contractions.
abstract: OBJECTIVE
  Many biological studies have been done to determine the activity of medicinal plants on gastrointestinal function. Since acetylcholine is the major transmitter involved in the gastrointestinal motility and there are some evidences regarding the cholinergic modulatory effect of hops extract, in the present study spasmolytic and antispasmodic action of hops (Humulus lupulus) on acetylcholine-induced contraction in isolated rat's ileum was evaluated.
  
  
  METHODS
  In this study, pieces of isolated rat's ileum were mounted in the internal chamber of an organ bath which was filled with Tyrode's solution and tightly tied to the lever of an isotonic transducer. The contractile responses were recorded by using an oscillograph device. In the presence of normal saline and different concentrations of hops (0.1, 0.3, and 0.5 mg/ml), the amplitude of contractions induced by10(-12) up to 10(-2) M acetylcholine was determined. The spasmolytic action of the same extract concentrations was also examined on contraction induced by 10(-4) acetylcholine.
  
  
  RESULTS
  Our findings indicate that hops extract reduces acetylcholine-induced contraction in all concentrations. The significant inhibitory effects of 0.1, 0.3, and 0.5 mg/ml hops extract on contraction induced by 10(-3) M acetylcholine were 81.9, 77, and 29.3, respectively (p<0.05).
  
  
  CONCLUSIONS
  According to our findings, hops extract poses a potent spasmolytic and antispasmodic action on acetylcholine-induced contraction in isolated rat's ileum which may be mediated by cholinergic systems.
authors: Department of Physiology/herbal Medicine Research Center, Shahid Sadoghi University of Medical Sciences, Yazd, I. R. Iran.
authors: Seyed Hassan
authors: SH
authors: Hejazian
authors: Department of Physiology/herbal Medicine Research Center, Shahid Sadoghi University of Medical Sciences, Yazd, I. R. Iran.
authors: Seyyed Majid
authors: SM
authors: Bagheri
authors: Department of Physiology/herbal Medicine Research Center, Shahid Sadoghi University of Medical Sciences, Yazd, I. R. Iran.
authors: Mohammad Hossein
authors: MH
authors: Dashti-R
keywords: Acetylcholine; Antispasmodic; Humulus lupulus; Ileum