Different Effects of Flavonoids in Scutellaria baicalensis on Anxious and Sedative Behaviors

  • Park Hyung-Geun (Department of Pharmacy, Sahmyook University) ;
  • Choi Ji-Young (Department of Pharmacy, Sahmyook University) ;
  • Lee Geum-Seon (Department of Pharmacy, Sahmyook University) ;
  • Choi Jong-Hyun (Department of Pharmacy, Sahmyook University) ;
  • Son Kun-Ho (Department of Food Science and Nutrition, Andong National University) ;
  • Yoon Seo-Young (Department of Pharmacy, Sahmyook University) ;
  • Ko Hong-Sook (Department of Pharmacy, Sahmyook University) ;
  • Ko Kwang-Ho (Department of Pharmacology, College of Pharmacy, Seoul National University) ;
  • Ryu Jong-Hoon (Department of Oriental Pharmaceutical Science, College of Pharmacy, KyungHee University) ;
  • Cheong Jae-Hoon
  • Published : 2006.06.01


The main aim of this study was to characterize the pharmacological profile of flavonoids utilizing behavioral tests and to investigate how the psychopharmacological activities of wogonin, baicalein and oroxylin A are different. Wogonin, baicalein and oroxylin A were intraperitoneally injected as dosages of 2.5, 5, 10 and 20 mg/kg. In the locomotor activity, Rota-rod test, and elevated plus-maze tests, the behavioral parameters were analyzed by automatic systems. Thiopental induced sleeping time was measured. Water extract of S. baicalensis didn't exhibit sedative effect. Wogonin and bacalein exhibited anxiolytic activity although it was less potent than buspirone. Wogonin and baicalein decreased locomotor activity at a dose of 10 mg/kg. Wogonin also shortened significantly running time on the rota-rod at doses of 5 and 10 mg/kg. Wogonin and baicalein enhanced sleeping at doses of 5 and 10 mg/kg. These results indicate that wogonin produce anxiolysis with sedation and so did bacalein with mild sedation. On the contrary, oroxylin A enhanced running activity on the rotarod and did't depress locomotor activity. Oroxylin A significantly hindered sleeping rather than helped it at doses of 5 and 10 mg/kg. Oroxylin A didn't produce anxiolysis and instead, produce awakening effect. This study demonstrates that wogonin and bacalein exhibited anxiolytic activity with mild sedation, but oroxylin A didn't produce anxiolysis and instead, produce awakening effect. This result indicates that anxiolytic effect without sedation induced by Scutellaria baicalensis is produced by combination of flavonoids.



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