title: Antispasmodic activity of licochalcone A, a species-specific ingredient of Glycyrrhiza inflata roots.
abstract: Licochalcone A, a species-specific and characteristic retrochalcone ingredient of Glycyrrhiza inflata root, has been shown to possess multiple bioactive properties. However, its muscle relaxant activity has not been reported previously. Licochalcone A showed a concentration-dependent relaxant effect on the contraction induced by carbachol (50% effective concentration (EC50) = 5.64 +/- 1.61 microM), KCl (EC50 5.12 +/- 1.68 microM), BaCl2 (EC50 1.97 +/- 0.48 microM) and A23187 (EC50 2.63 +/- 2.05 microM). Pretreatment with licochalcone A enhanced the relaxant effect of forskolin, an adenylyl cyclase activator, on the contraction in a similar manner to 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase (PDE) inhibitor. Furthermore, the IC50 (22.1 +/- 10.9 microM) of licochalcone A against cAMP PDE was similar to that of IBMX (26.2 +/- 7.4 microM). These results indicated that licochalcone A may have been responsible for the relaxant activity of G. inflata root and acted through the inhibition of cAMP PDE.
authors.affiliation: Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Hidemasa
authors.initials: H
authors.lastname: Nagai
authors.forename: Ju-Xiu
authors.initials: JX
authors.lastname: He
authors.forename: Tadato
authors.initials: T
authors.lastname: Tani
authors.forename: Teruaki
authors.initials: T
authors.lastname: Akao
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D047188:Chalcones / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006035:Glycyrrhiza / Q000737:chemistry*; D066298:In Vitro Techniques; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009119:Muscle Contraction / Q000187:drug effects*; D010276:Parasympatholytics / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018517:Plant Roots; D010946:Plants, Medicinal; D013035:Spasm / Q000188:drug therapy
chemical_list: D047188:Chalcones; D010276:Parasympatholytics; D010936:Plant Extracts; C070840:licochalcone A; D015056:1-Methyl-3-isobutylxanthine