Effects of Valeriana officinalis extracts on [3H]flunitrazepam binding, synaptosomal [3H]GABA uptake, and hippocampal [3H]GABA release

Neurochem Res. 1999 Nov;24(11):1373-8. doi: 10.1023/a:1022576405534.


Extracts of Valeriana officinalis have been used in folkloric medicine for its sedative, hypnotic, tranquilizer and anticonvulsant effects, and may interact with gamma-aminobutyric acid (GABA) and/or benzodiazepine sites. At low concentrations, valerian extracts enhance [3H]flunitrazepam binding (EC50 4.13 x 10(-10) mg/ml). However, this increased [3H]flunitrazepam binding is replaced by an inhibition at higher concentrations (IC50 of 4.82 x 10(-1) mg/ml). These results are consistent with the presence of at least two different biological activities interacting with [3H]flunitrazepam binding sites. Valerian extracts also potentiate K+ or veratridine-stimulated release of radioactivity from hippocampal slices preloaded with [3H]GABA. Finally, inhibition of synaptosomal [3H]GABA uptake by valerian extracts also displays a biphasic interaction with guvacine. The results confirm that valerian extracts have effects on GABA(A) receptors, but can also interact at other presynaptic components of GABAergic neurons.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Drug Synergism
  • Female
  • Flunitrazepam / metabolism*
  • GABA Modulators / metabolism
  • Hippocampus / drug effects
  • Hippocampus / metabolism*
  • Medicine, Traditional
  • Mice
  • Plant Extracts / pharmacology*
  • Plants, Medicinal*
  • Potassium / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Synaptosomes / drug effects
  • Synaptosomes / metabolism*
  • Tritium
  • Veratridine / pharmacology
  • gamma-Aminobutyric Acid / metabolism*


  • GABA Modulators
  • Plant Extracts
  • Tritium
  • gamma-Aminobutyric Acid
  • Flunitrazepam
  • Veratridine
  • Potassium