Fig. 7.

The relationship between constitutive activity and stabilization energy contributed by propofol. The value for the change in energy for constitutive gating is plotted against the change in stabilization energy contributed by propofol binding for 24 pairs of receptors in which a single mutation was introduced. The linear regression slope is −1.2 ± 0.2 (R² = 0.60; P value for hypothesis that slope is actually zero = 8 × 10⁻⁶). The slope for the β2(Y143W) mutations is −0.9 ± 0.3, and that for the β2(M286W) mutations is −1.2 ± 0.3; the slopes do not differ (P = 0.4).