Fig. 3.

Inhibition of the 5-HT₃ receptor by citral, eucalyptol, or linalool. 5-HT–induced currents were measured at −60 mV in the absence or presence of various concentrations of citral (A), eucalyptol (B), or linalool (C) following a 30-second preapplication. The data were analyzed as described in the text, and the output of this nonlinear mixed-effects modeling is shown in Table 1. The main features of the structural model are illustrated here. The dotted lines show the effect of the compounds on the EC₅₀. The insets show normalized data at the same inhibitor concentrations; for citral and linalool, the apparent shifts in the EC₅₀ seen in this normalized data are artifacts caused by the normalization. Additional data at 10, 30, 300, 600, and 1000 µM citral and 200 and 660 µM eucalyptol were also collected, but the curves are omitted for clarity.