Figure 13.

Relationship between in vitro γ-aminobutyric acid type A (GABA_A) receptor and in vivo hypnotic potencies of etomidate and etomidate analogues. Each compound’s GABA_A receptor potency is defined as the half-maximal direct activating concentration (EC₅₀) and its hypnotic potency is defined as the median effective dose that produces loss of righting reflexes in rats (ED₅₀). The dashed line is a linear fit of the logarithm-transformed data. The slope of the fitted line was 1.22 ± 0.18 and the coefficient of determination (r²) was 0.72.