Abstract
Active compounds of Ginkgo biloba extract (ginkgolides A, B, C, and J) were tested on the main ligand-operated conductances in rat neurons using a patch-clamp technique in the whole-cell configuration and a concentration-clamp technique. It was found that all ginkgolides reduced glycine-activated currents in concentration- and use-dependent manners, whereas they did not affect other tested ligand-gated receptors (NMDA- and GABA-activated ones). The IC50 values calculated from dose-response curves were as follows: 1.97, 0.273, 0.267, and 2.0 μM for ginkgolides A, B, C, and J, respectively (200 μM Gly ).The Hill coefficient in all cases was close to 1.0, which indicates a single site of the drug binding to the glycine-activated receptor.
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Kondratskaya, E.L., Krishtal, O.A. Effects of Ginkgo Biloba Extract Constituents on Glycine-Activated Strychnine-Sensitive Receptors in Hippocampal Pyramidal Neurons of the Rat. Neurophysiology 34, 155–157 (2002). https://doi.org/10.1023/A:1020774410527
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DOI: https://doi.org/10.1023/A:1020774410527