Selective γ‐hydroxybutyric acid receptor ligands increase extracellular glutamate in the hippocampus, but fail to activate G protein and to produce the sedative/hypnotic effect of γ‐hydroxybutyric acid

@article{Castelli2003SelectiveA,
  title={Selective $\gamma$‐hydroxybutyric acid receptor ligands increase extracellular glutamate in the hippocampus, but fail to activate G protein and to produce the sedative/hypnotic effect of $\gamma$‐hydroxybutyric acid},
  author={Maria Paola Castelli and Luca Ferraro and Ignazia Mocci and Francesca Carta and Mauro A. M. Carai and Tiziana Antonelli and Sergio Tanganelli and Giorgio Cignarella and Gian Luigi Gessa},
  journal={Journal of Neurochemistry},
  year={2003},
  volume={87}
}
Two γ‐hydroxybutyric acid (GHB) analogues, trans‐γ‐hydroxycrotonic acid (t‐HCA) and γ‐(p‐methoxybenzyl)‐γ‐hydroxybutyric acid (NCS‐435) displaced [3H]GHB from GHB receptors with the same affinity as GHB but, unlike GHB, failed to displace [3H]baclofen from GABAB receptors. The effect of the GHB analogues, GHB and baclofen, on G protein activity and hippocampal extracellular glutamate levels was compared. While GHB and baclofen stimulated 5′‐O‐(3‐[35S]thiotriphospate) [35S]GTPγS binding both in… 

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