Fig. 5. Gabazine-induced increase in muscle force after an EC⁵⁰acetylcholine contraction and antagonism of gabazine’s effect by the γ-aminobutyric acid channel subtype A channel (GABA^A) agonist muscimol are dose-dependent. (  A ) Cumulatively increasing concentrations of gabazine (from 0 to 800 μm) result in a significant increase in muscle force above a sustained EC⁵⁰acetylcholine contraction with an IC⁵⁰of 163 μm (n = 12). **  P < 0.01 compared to time controls (no gabazine treatment); ***  P < 0.001 compared to time controls. (  B ) Cumulatively increasing concentrations of the GABA^Achannel agonist muscimol (0–800 μm) after a fixed dose of gabazine (200 μm) demonstrates significant reversal of the achieved GABA^Achannel antagonism in a dose-dependent fashion (n = 4–8). *  P < 0.05, **  P < 0.01, ***  P < 0.001 compared to no treatment.