gamma-Hydroxybutyrate induces cyclic AMP-responsive element-binding protein phosphorylation in mouse hippocampus: an involvement of GABA(B) receptors and cAMP-dependent protein kinase activation

Neuroscience. 2006 Aug 11;141(1):269-75. doi: 10.1016/j.neuroscience.2006.03.056. Epub 2006 May 3.

Abstract

gamma-Hydroxybutyrate is a widely used recreational drug. Its abuse has been associated with cognitive impairments and development of tolerance and dependence. However, the neural mechanisms underlying these effects remain unclear. In the present study we investigated the possible cellular signaling mechanisms that might mediate gamma-hydroxybutyrate's action. Acute administration of gamma-hydroxybutyrate (500 mg/kg, i.p.) was found to cause a rapid and long-lasting increase in the phosphorylation level of the cAMP-responsive element-binding protein in mouse (C57/BL6) hippocampus. Pretreatment with the specific GABA(B) receptor antagonist [3-[1-(R)-[(3-cyclohexylmethyl)hydroxyphosphinyl]-2-(S)-hydroxy-propyl]amino]ethyl]-benzoic acid (20 mg/kg, i.p.) prevented the action of gamma-hydroxybutyrate, confirming a GABA(B) receptor-mediated mechanism. In addition, acute gamma-hydroxybutyrate administration induced a significant increase in cytosolic cAMP-dependent protein kinase activity in the hippocampus, and pretreatment with the cAMP-dependent protein kinase inhibitor H-89 could prevent the effect of gamma-hydroxybutyrate on cAMP-responsive element-binding protein phosphorylation, indicating a direct involvement of cAMP-dependent protein kinase in gamma-hydroxybutyrate-induced cAMP-responsive element-binding protein phosphorylation. On the other hand, the increased expression of phosphorylated cAMP-responsive element-binding protein was not observed in the hippocampus of mice subjected to repeated gamma-hydroxybutyrate exposure, suggesting the development of a gamma-hydroxybutyrate-induced desensitization of the signaling pathway leading to cAMP-responsive element-binding protein activation. Since cAMP-responsive element-binding protein activation has been implicated in a variety of neural plasticities, our findings may have revealed a new mechanism underlying gamma-hydroxybutyrate-induced neuroadaptations.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Anesthesia / pharmacology*
  • Animals
  • Blotting, Western / methods
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Drug Interactions
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / pharmacology
  • GABA Antagonists / pharmacology
  • Hippocampus / drug effects*
  • Mice
  • Mice, Inbred C57BL
  • Phosphinic Acids / pharmacology
  • Phosphorylation / drug effects
  • Receptors, GABA-A / physiology*
  • Sodium Oxybate / pharmacology*
  • Time Factors

Substances

  • Adjuvants, Anesthesia
  • CGP 56999A
  • Cyclic AMP Response Element-Binding Protein
  • Enzyme Inhibitors
  • GABA Antagonists
  • Phosphinic Acids
  • Receptors, GABA-A
  • Sodium Oxybate
  • Cyclic AMP-Dependent Protein Kinases