Extensive Heterogeneity of Recombinant γ-Aminobutyric Acid A Receptors Expressed in α 4 β 3 γ 2 -Transfected Human Embryonic Kidney 293 Cells

摘要: Abstract Human embryonic kidney 293 cells transiently transfected with α 4 -, β 3 - and γ 2 -subunits of γ-aminobutyric acid A (GABA ) receptors from the rat exhibited specific high affinity binding sites for [ H]muscimol, H]Ro 15-4513 35 S] t -butylbicyclophosphorothionate (TBPS). B max values obtained, however, were dramatically different these compounds. In addition, GABA was able to inhibit only 20% S]TBPS membranes -transfected cells. order investigate possible receptor heterogeneity, extracted fractionated by chromatography on an anti-γ followed anti-α anti-β -immunoaffinity column. Western blot analysis column eluates indicated separate existence consisting or in This, finding that but not -receptors possess all three radiolabeled ligands investigated, combined observation cannot be inhibited GABA, can explain most data obtained. The present results suggest inefficient assembly and/or subunits under conditions used, indicate recombinant expressed HEK are necessarily homogeneous. Copyright © 1996 Elsevier Science Ltd