Figure 8. The binding effects of both anesthetic and nonanesthetic volatile compounds are directly proportional to anesthetic potencies predicted by the Meyer - Overton correlation. The “half” inhibitory concentrations (IC50s) for inhibition of wild-type nicotinic acetylcholine receptors (nAChRs) currents (open symbols), or [Greek small letter alpha] S252I +[Greek small letter beta] T263I nAChR currents (solid symbols) are from Table 3or from Dilger et al., [20]and Kds for quenching hSA fluorescence (batched symbols) are from Table 4. Meyer-Overton predicted EC50s for anesthesia in rats are from Table 3and Table 4or calculated as described by Raines. [11]Each volatile compound is represented by a different symbol: enflurane is an upward triangle; isoflurane is a downward triangle); halothane is a diamond; chloroform is an X; F6 is a square; F8 is a circle. Lines drawn through data points are linear least-squares fits. Wild-type nAChR IC50: slope = 0.96 +/- 0.076; mutant nAChR IC50: slope = 0.82 +/- 0.075; hSA Kd: slope = 0.82 +/- 0.19.