FIGURE 5.

Normalized currents showing the effect of 12 sensory active compounds isolated from black peppercorns (see Figure 1) at 1 mM on Xenopus laevis oocytes expressing hKCNK3 (A), hKCNK 9 (B), and hKCNK18 (C). N = 3–7 oocytes. The currents were normalized to the current registered prior to the application of each substance (dotted black line, see materials and methods section for further details). If a substance was able to induce a change greater than 20% of the basal activity (as indicated by upper and lower dotted lines), the effect was considered relevant. For all graphics, the reported effect of 1 mM piperine is provided as a reference (gray bar).