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PubMed · 11711039

gamma-Hydroxybutyric acid and baclofen decrease extracellular acetylcholine levels in the hippocampus via GABA(B) receptors.

F Nava·G Carta·M Bortolato·G L Gessa
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Abstract

The effect of gamma-hydroxybutyric acid (GHB) and baclofen, a GABA(B) receptor agonist, on extracellular hippocampal acetylcholine levels was studied in freely moving rats by microdialysis. GHB (200 and 500 mg/kg, i.p.) reduced in a dose-dependent manner, extracellular hippocampal acetylcholine concentrations and this effect was prevented by the GABA(B) receptor antagonist (2S)(+)-5,5-Dimethyl-2-morpholineacetic acid (SCH 50911), at the dose of 20 mg/kg (i.p.), while the putative GHB receptor antagonist 6,7,8,9-Tetrahydro-5-hydroxy-5H-benzocyclohept-6-ylideneacetic acid (NCS 382) was ineffective. Similar to GHB, the GABA(B) agonist baclofen (10 and 20 mg/kg, i.p.) produced a dose-related reduction in extracellular acetylcholine concentrations which was prevented by SCH 50911. These findings indicate that GHB-induced reduction of hippocampal acetylcholine release is mediated by GABA(B) receptors and support a possible involvement of hippocampal GABA(B) receptors in the control of cognitive processes and in the claimed amnesic effect of GHB intoxication.

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AcetylcholineAnimalsAnticonvulsantsBaclofenBenzocycloheptenesDose-Response Relationship, DrugExtracellular SpaceGABA AgonistsGABA AntagonistsHippocampusHydroxybutyratesMaleMorpholinesRatsRats, Sprague-DawleyReceptors, GABA-BTime FactorsJournal Article

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F Nava, G Carta, M Bortolato, G L Gessa. 2001-11-02. gamma-Hydroxybutyric acid and baclofen decrease extracellular acetylcholine levels in the hippocampus via GABA(B) receptors.. https://doi.org/10.1016/s0014-2999(01)01163-3

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