Fig. 3. Effects of 10 μM etomidate versus  19 μM propofol on GABA concentration-responses. Data points are mean ± SD measurements of peak currents in at least 5 oocytes per condition, normalized to responses elicited with 10 mM γ-aminobutyric acid (GABA) in the absence of anesthetics. Lines  drawn through data represent nonlinear least-squares method fits to logistic functions (Equation 1, see Materials and Methods). Fitted parameters are reported as best fit (95% CI). (A ) Control GABA responses (red squares ) and responses in the presence of 10 μM etomidate (ETO; blue squares ). Control: Maximum = 101% (98–102); EC⁵⁰= 105 μM (95–116 μM); Hill slope = 1.23 (1.10–1.35). With ETO: Maximum = 125% (121–129); EC⁵⁰= 4.3 μM (3.8–4.9 μM); Hill slope = 1.25 (1.07–1.42). The EC⁵⁰ratio (ETO/control) = 0.041 (0.034–0.048). (B ) Control GABA responses (red circles ) and responses in the presence of 19 μM propofol (PRO; blue circles ). These data were obtained with different cells from those used for ETO. Control: Maximum = 102% (99–105); EC⁵⁰= 97 μM (86–109 μM); Hill slope = 1.3 (1.13–1.48). With PRO: Maximum = 125% (122–128); EC⁵⁰= 4.2 μM (3.6–4.8 μM); Hill slope = 1.3 (1.11–1.51). The EC⁵⁰ratio (PRO/control) = 0.043 (0.036–0.051). ETO = etomidate; GABA = γ-aminobutyric acid; PRO = propofol.