Gamma-hydroxybutyrate is a weak agonist at recombinant GABA(B) receptors.

阅读量：

作者：

K Lingenhoehl，R Brom，J Heid，P Beck，J Mosbacher

展开

摘要：

Gamma-hydroxybutyrate (GHB) is a neuromodulator with high affinity binding sites in the mammalian brain. However, the receptor for GHB has not yet been identified. There are indications that GHB and gamma-aminobutyric acid (GABA) mediate their effects via the same receptor. We tested this hypothesis using GABA(B)R1/R2 receptors co-expressed with Kir3 channels in Xenopus oocytes. GHB activated these receptors with an EC50 of approximately 5 mM and a maximal stimulation of 69% when compared to the GABA(B) receptor agonist L-baclofen. GHB and L-baclofen did not amplify each others effect nor did they stimulate the GABA(B) receptor in a linearly additive manner. CGP54626A, 2-OH saclofen and CGP35348, three competitive GABA(B) receptor antagonists, inhibited the GHB induced response completely. A concentration of 30 mM GHB displaced [125I]CGP64213 binding at GABA(B)R1 expressed in COS cells by 21%. These results indicate that GHB is a weak partial agonist at the GABA binding site of GABA(B)R1/R2.

展开

关键词：

gamma-hydroxybutyrate gamma-aminobutyrate GABA(B) receptor Xenopus oocytes electrophysiology

DOI：

10.1016/S0028-3908(99)00131-8

被引量：

314

年份：

1999