Polyclonal antibodies were raised to synthetic amino acid sequences of the bovine GABAA receptor α2- and α3-subunits and purified by affinity chromatography on a column coupled with the respective peptide. Anti-peptide α2(416–424) and anti-peptide α3(459–467) antibodies immunoprecipitated GABAA receptors and recognized a protein of 53 kDa (P53) and 59 kDa (P59), respectively, in Western blots of GABAA receptors purified from the brains of 5–10 day old rats. P53 as well as P59 are specifically photolabeled by [3H]flunitrazepam and are recognized by the α-subunit specific monoclonal antibody bd 28.
