FIGURE 10.

MRGPR-X1-induced TRPV1 activation requires the PIP₂ binding site of the TRPV1. Ca²⁺ signals in fura2-loaded F11-MRGPR-X1 cells and TRPV1-YFP or TRPV1-δ777–820-YFP co-expressing F11-MRGPR-X1 cells were monitored. CAP (10 nm, final) (A), BAM8–22 (2 μm, final) (B), and BK (100 nm, final) (C) were manually injected at time point 50 s. Data from 3–5 independent experiments were compiled, normalized by defining the first value (0.5 s) measured as 100%, and expressed as the mean ± S.E. The AUC for each measured cell was determined, data of all cells compiled, expressed as the mean ± S.E. and presented in bar graphs. Asterisks (***, p < 0.001) indicate a significant difference between TRPV1-δ777–820-YFP co-expressing F11-MRGPR-X1 and F11-MRGPR-X1/TRPV1 cells; hash signs (###, p < 0.001) between F11-MRGPR-X1 and TRPV1-δ777–820-YFP co-expressing F11-MRGPR-X1 cells.