Selective Interactions of Valeriana officinalis Extracts and Valerenic Acid with [³H]Glutamate Binding to Rat Synaptic Membranes

Figure 2

Effects of valerian extracts, valerenic acid, and isoborneol on ionotropic glutamate receptors (iGluR). (a) Valerian extract at 0.05 mg/ml in presence of 1 mM kainic acid (KA) decreased the glutamate binding significantly. This effect was not seen with NMDA or AMPA. High concentrations of valerian extract (10 mg/ml) in presence of NMDA (1 mM) significantly decreased the glutamate binding. Neither AMPA nor KA in presence of higher valerian extract concentrations affected the binding. (b) Valerenic acid at 0.008 mg/mL, in presence of 1 mM NMDA, kainic acid (KA) and AMPA, did not affect the glutamate binding. (c) Isoborneol at 0.0008 mg/mL, in presence of 1 mM NMDA, significantly decreased the glutamate binding. At higher concentration (1 mg/mL), isoborneol markedly decreased the glutamate binding in presence of AMPA and KA. ⁺ agonist versus agonist + (valerian, valerenic acid, or isoborneol), 𝑃<.05;⁺⁺𝑃<.01;⁺⁺⁺𝑃<.001.