Changes in hippocampal GABAA receptor subunit composition in bipolar 1 disorder

Abstract

Postmortem CNS studies have suggested an uncoupling of the γ-aminobutyric acid (GABA) and benzodiazepine binding sites on the hippocampal GABAA receptor in schizophrenia. The GABAA receptor is an assembly of discrete subunits that form a ligand-gated ion channel, the binding characteristics of which are defined by receptor subunit composition. Thus, a likely explanation for an uncoupling between the GABA and benzodiazepine binding sites on the GABAA receptor would be a change in receptor subunit composition. To test this hypothesis we measured the density of GABA ([3H]muscimol) and benzodiazepine ([3H] flumazenil) binding sites on the GABAA receptor in hippocampi, obtained postmortem, from s..