Figure 5.

GABA and DA function is preserved in receptors with ^Zβ3 subunits. A, Close-up overhead views of the human β3 homopentamer channel pore emphasizing H267 or H267A (space-filling models). Note the presence (left) and absence (right) of Zn²⁺-coordinating imidazole side chains. B, Traces and quantitative analysis of GABA concentration–response curves in cells transfected with α1β3γ2 or α1^Zβ3γ2 receptors. The plot shows mean ± SEM for GABA-evoked amplitudes compared with 300 μm. C, Traces and analysis of concentration–response curves for DA (filled bars) compared with GABA (0.1 mm, unfilled bars) in α1^Zβ3γ2-transfected or α1^Zβ3-transfected cells. Quantified data represent mean ± SEM for evoked currents from DA compared with GABA.