ABSTRACT
This chapter reviews the structural complexity of the γ-aminobutyric acidA (GABAA) receptor family and the pharmacological evidence that was a prelude to its investigation using biochemical techniques. Western blotting with antibodies against identified subunits of the GABAA receptor has shown the different bands irreversibly labelled with [H]-flunitrazepam to be the different isoforms of the a subunit of the receptor. The solubilisation and purification of the GABAA receptor from bovine brain proved to be a watershed in subsequent molecular biological studies of this receptor. In attempts to isolate additional cDNA clones encoding GABAA receptor subunits, Seeburg and co-workers used an alternate strategy. A further mechanism for the generation of heterogeneity within the GABAA receptor subunit isoforms has been revealed by the identification of alternate splice variants. Antibody precipitation or affinity purification, in conjunction with Western blot of the purified products, has proved invaluable in the analysis of the GABAA receptor subtypes that exist in vivo.
