GABA(A) ρ receptor mechanisms in the rat amygdala and its role in the modulation of fear and anxiety

Psychopharmacology (Berl). 2010 Dec;212(4):475-84. doi: 10.1007/s00213-010-1973-x. Epub 2010 Aug 6.


Rationale: Accumulating evidence for the presence of GABA(A) ρ receptors within the amygdala which differ from other members of the GABA(A) receptor family in both subunit composition and functional properties has been recently obtained.

Objectives: This work was conducted to study whether GABA(A) ρ receptors may have a putative role in the amygdaloid modulation of fear and anxiety.

Results: It was found that the bilateral intra-amygdaloid administration (6-240 pmol/side) of (1,2,5,6-tetrahydropyridine-4-yl)methylphosphinic acid, a selective GABA(A) ρ receptor antagonist, reduced dose-dependently the exploration of the open arms of the elevated plus-maze without affecting locomotion and increased the plasma levels of corticosterone. In contrast, bicuculline in the dose range used (1.8-60 pmol/side) induced seizures, but had no effects on the exploration of the maze.

Conclusions: It is suggested that GABA(A) ρ receptors may have a role in the amygdaloid modulation of fear and anxiety.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amygdala / drug effects
  • Amygdala / metabolism*
  • Animals
  • Anxiety / metabolism*
  • Behavior, Animal* / drug effects
  • Bicuculline / administration & dosage
  • Bicuculline / adverse effects
  • Corticosterone / blood
  • Dose-Response Relationship, Drug
  • Exploratory Behavior / drug effects
  • Fear* / drug effects
  • GABA-A Receptor Antagonists / administration & dosage
  • GABA-A Receptor Antagonists / adverse effects
  • Male
  • Microdialysis
  • Motor Activity / drug effects
  • Phosphinic Acids / administration & dosage
  • Pyridines / administration & dosage
  • Rats
  • Rats, Wistar
  • Receptors, GABA-A / drug effects
  • Receptors, GABA-A / metabolism*
  • Seizures / chemically induced


  • (1,2,5,6-tetrahydropyridin-4-yl)methylphosphinic acid
  • GABA-A Receptor Antagonists
  • Phosphinic Acids
  • Pyridines
  • Receptors, GABA-A
  • Corticosterone
  • Bicuculline