Planta Medica, Table of Contents Planta Med 2002; 68(12): 1059-1062DOI: 10.1055/s-2002-36357 Original PaperPharmacology© Georg Thieme Verlag Stuttgart · New YorkStructure-Activity Relationships of Flavonoids, Isolated from Scutellaria baicalensis, Binding to Benzodiazepine Site of GABAA Receptor ComplexHongyan Wang1, 2 , Kwok-Min Hui2 , Yingjie Chen1 , Suixu Xu1 , J. Tze-Fei Wong2 , Hong Xue2 1Department of Natural Product Chemistry, Shenyang Pharmaceutical University, P.R.China 2Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong Recommend Article Abstract Buy Article(opens in new window) Abstract Twenty-six flavonoids were isolated from Scutellaria baicalensis. Their affinities for the benzodiazepine (BDZ) binding site of GABAA receptor have been studied using [3 H]flunitrazepam binding to rat cortical membranes in vitro. The structure-activity relationships suggested that 2′-OH flavones exhibited the most potent binding affinity, which could lead to the design and discovery of new BDZ receptor ligands. Key words Flavonoids - Scutellaria baicalensis - Lamiaceae - BDZ receptor ligands - structure-activity relationship Full Text References References 1 Wolfman C, Viola H, Paladini A, Dajas F, Medina J H. Possible anxiolytic effects of chrysin, a central benzodiazepine receptor ligand isolated from Passiflora coerulea . Pharmacology Biochemistry and Behavior. 1994; 47 1-4 2 Viola H, Wasowski C,Leride Stein M, Wolfman C, Silveira R, Dajas F, Medina J H, Paladini A C. Apigenin, a component of Matricaria recutita flowers, is a central benzodiazepine receptors-ligands with anxiolytic effects. Planta Med.. 1995; 61 213-6 3 Salgueiro J B, Ardenghi P, Dias M, Ferreira M BC, Izquierdo I, Medina J H. 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