Relaxant effect of Humulus lupulus extracts on isotonic rat's ileum contractions

Document Type : Original Research Article


Department of Physiology/herbal Medicine Research Center, Shahid Sadoghi University of Medical Sciences, Yazd, I. R. Iran


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.
Material and 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).
Conclusion: 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.


Main Subjects

Chadwick LR, pandi GF, Farnsworth NR. 2006. The pharmacognosy of Humulus Lupulus Hops with an emphasis of estrogenic properties. Phytomedicine, 13: 119-131.
Chen Qh, Ming-liang F, Chen MM, Liu J, Liu X, He G, Pu S. 2012. Preparative isolation and purification of xanthohumol from hops (Humulus lupulus L.) by high-speed counter-current chromatography. J Ethnopharmacol, 132: 619-623.
Dimpfel W, Suter Dimpfel W, Suter A. 2008. Sleep improving effects of a single dose administration of a valerian/hops fluid extract - a double blind, randomized, placebo-controlled sleep-EEG study in a parallel design using electrohypnograms. Eur J Med Res, 13: 200-204.
Dimpfel W, Brattström A, Koett U. 2006. Central action of fixed Valerian-hops extract combination (Ze 91019) in freely moving rats. Eur J Med Res, 11: 496-500.
Estrada-Soto S, Sánchez-Recillas A, Navarrete-Vázquez G, Castillo-España P, Villalobos-Molina R, Ibarra-Barajas M. 2012. Relaxant effects of Artemisia ludoviciana on isolated rat smooth muscle tissues. J Ethnopharmacol, 139: 513-518.
Hansel R, Wohlfart R, Coper H. 1980. Sedative-hypnotic compounds in the exhalation of hops, II (in German). Z Naturforsch C, 35: 1096-1097.
Hitoshi A, Katsuichi T, Yoichi O, Sheikh Julfikar H, Hirofumi K, Yoshinobu K. 2006. Effects of Beer and Hop on Ionotropic γ-Aminobutyric Acid Receptors. J Agri Food Chem, 54:2514-2519.
Hejazian SH, Mahdavi SM. 2007. Comparison between the analgesic effect of Humulus lupulus (Hops) extract and Morphine in Mice. J Rafsanjan Univ Med Sci, 5: 273-278.
Hejazian SH, Dashti MH, Mahdavi SM, Qureshi MA. 2009. The effect of Carum Copticum Extract on Acetylcholine Induced Contraction in isolated rat's ileum. J Acupunct Meridian Stud, 2: 75-78. 
Hejazian SH, Sepehri H, Dashti MH, Mahdavi SM, Bagheri SM,  Morshedi A, Rezvani MH, Ali SA, Ali MS. 2011. Does essential oil of Carum copticum affect acetylcholine-induced contraction in isolated rat's Ileum? J Pharm Pharmacol, 5: 1432-1435.
Juanez JC. 2012. Hops (Humulus lupulus L.) and Beer: Benefits on the Sleep. J Sleep Disord Ther, 1: 102.
Kavalier AR, Litt A, Chunhui  MA,  Nicholi J,  Pitra MC, Edward J, Matthews PD. 2011. Phytochemical and Morphological Characterization of Hops (Humulus lupulus L.) Cones over Five Developmental Stages Using High Performance Liquid Chromatography Coupled to Time-of-Flight Mass Spectrometry, Ultrahigh Performance Liquid Chromatography Photodiode Array Detection, and Light Microscopy Techniques. J Agri Food Chem, 59: 4783-4793.
Kanako A, Yumi N, Hana H, Kiyohito K, Kentaro M. 2007. Cells expressing GABA synthetic enzyme, glutamate decarboxylase, in stomach and intestine: RT-PCR and immunohistochemistry studies. J Biol Macromol, 7: 55-62.
Kawakami S, Uezono Y, Makimoto N, Enjoji A, Kaibara M, Kanematsu T, Taniyama K. 2004. Characterization of GABA (B) receptors involved in inhibition of motility associated with acetylcholine release in the dog small intestine: possible existence of a heterodimer of GABA (B1) and GABA (B2) subunits. J Pharm Sci, 94: 368-375.
Koniger C, Worek F, Thiermann H, Wille T. 2013. Effect of MB327 and oximes on rat intestinal smooth muscle function.  Chem Biol Interact, 204: 1-5.
Kurasawa T, Chikaraishi Y, Naito A, Toyoda Y, Notsu Y. 2005. Effect of humulus lupulus on gastric secretion in a rat pylorus-ligated model. Biol Pharm Bull, 28: 353-357.
Kurjak M, Fichna J, Harbarth J, Sennefelder  A, Allescher HD, Schusdziarra V, Storr MOtto B. 2011. Effect of GABA-ergic mechanisms on synaptosomal NO synthesis and the nitrergic component of NANC relaxation in rat ileum. J Neurogastroenterol Motil, 23: 181-190.
Kutchai HC. Digestive system. 2006. In: Stanton, B.A., Koepen, B.M., Editors. Berne & Levy. Principles of physiology. Philadelphia: elsevior Mosby, 435-437.
Muller-Limmroth W, Ehrenstein W. 1997. Experimental studies of the effects of Valerian, Hops and Poison flower on subjects suffering from anxiety disorders. MED KLIN, 72: 1119-1125.
Natividad GM, Broadley KJ,  Kariuki B, Kidd  EJ,  Ford  WR,  Simons C.  2011. Actions of Artemisia vulgaris extracts and isolated sesquiterpene lactones against receptors mediating contraction of guinea pig ileum and trachea.  J Ethnopharmacol, 137: 808-816.
Qasemi D. 2003. Iranian Herbal Pharmacopoeia. 1th ed. health sciences ministry. 
Reeves PA, Richards CM. 2011. Species Delimitation under the General Lineage Concept: An Empirical Example Using Wild North American Hops (Cannabaceae: Humulus lupulus). Syst Biol, 60: 45-59.
Ross SM. 2009. Sleep disorders: a single dose administration of valerian/hops fluid extract (dormeasan) is found to be effective in improving sleep. Holist Nurs Pract, 23: 253-256.
Roberts SJ, Papaioannou M, Evans BA, Summers RJ. 1999. Characterization of beta -adrenoceptor mediated smooth muscle relaxation and the detection of mRNA for beta1-, beta2- and beta3-adrenoceptors in rat ileum. Br J Pharmacol, 127: 949-961.
Segawa S, Takata Y, Wakita Y, Kaneko T, Kaneda H, Watari J, Enomoto T, Enomoto T. 2007. Clinical Effects of a Hop Water Extract on Japanese cedar Pollinosis during the Pollen Season: A Double-Blind, Placebo-Controlled Trial. Biosci Biotechnol Biochem, 8: 1955-1962.
Van Crombruggen K, Van Nassauw L, Timmermans JP, Lefebvre RA. 2007. Inhibitory purinergic P2 receptor characterisation in rat distal colon. Neuropharmacology, 53: 257-271.
Viesti VD, Carnevalea G, Zavattib M, Benellib A, Paola Z. 2011. Increased sexual motivation in female rats treated with Humulus lupulus L. extract. J Ethnopharmacol, 134: 514-517.