Anxiolytic activity of a phytochemically characterized Passiflora incarnata extract is mediated via the GABAergic system

Planta Med. 2008 Dec;74(15):1769-73. doi: 10.1055/s-0028-1088322. Epub 2008 Nov 12.


The purpose of this research was to assess the anxiolytic properties of a phytochemically characterized commercial extract from Passiflora incarnata (PI; Passifloraceae) in the elevated plus maze test in mice. Using an HPLC method, the flavonoids homoorientin, orientin, vitexin, and isovitexin were identified as major compounds. Following oral administration, the extract exerted an anxiolytic effect that was comparable to diazepam (1.5 mg/kg) at a dose of 375 mg/kg and exhibited a U-shaped dose-response curve. In addition, antagonism studies using the GABA (A)/benzodiazepine receptor antagonist flumazenil and the 5-HT (1A)-receptor antagonist WAY-100 635 were conducted. The active dose was effectively antagonized by flumazenil, but not by WAY-100 635. This study is the first demonstration of the IN VIVO, GABA-mediated anxiolytic activity of an HPLC- characterized extract of Passiflora incarnata.

MeSH terms

  • Animals
  • Anti-Anxiety Agents / pharmacology*
  • Buspirone / pharmacology
  • Chromatography, High Pressure Liquid / methods
  • Diazepam / pharmacology
  • Flavonoids / pharmacology
  • Flumazenil / pharmacology
  • GABA Modulators / pharmacology*
  • GABA-A Receptor Antagonists
  • Maze Learning / drug effects*
  • Mice
  • Mice, Inbred C57BL
  • Passiflora*
  • Phytotherapy*
  • Piperazines
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Pyridines
  • Serotonin Antagonists / pharmacology


  • Anti-Anxiety Agents
  • Flavonoids
  • GABA Modulators
  • GABA-A Receptor Antagonists
  • Piperazines
  • Plant Extracts
  • Pyridines
  • Serotonin Antagonists
  • Flumazenil
  • N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide
  • Diazepam
  • Buspirone