Figure 2.

Capsaicin inhibits pressure- and shear-sensitivity of Na_V1.5. (a), Representative Na_V1.5 currents elicited by voltage ladders ranging −100 to 0 mV in a cell-attached patch (a) or −120 mV to −30 mV in a whole cell (b), recorded at rest (filled symbols) or with force (empty symbols), in the presence of 0 µM (black) or 20 µM capsaicin (red). Difference currents were constructed by subtracting the control Na⁺ currents from the pressure- (a) or shear-stimulated (b) currents. (c-d), Steady-state activation (c) and inactivation (d) curves of Na⁺ currents in cell-attached patches (left) or whole cells (right), recorded at rest (filled symbols) or with force (empty symbols), in the presence of 0 µM (black) or 20 µM capsaicin (red). (e-h), Maximum peak Na⁺ current (e), time constant of activation (f), and voltage dependence of activation (g, V_1/2A) or inactivation (h, V_1/2I), recorded with 0 or −30 mmHg pressure in the patch (left) and 0 or 10 mL/min flow rate in whole cells (right) in the presence of 0 µM (black) or 20 µM capsaicin (red). n = 12–24 cells, *P < 0.05 comparing 0 to −30 mmHg or 0 to 10 mL/min, †P < 0.05 comparing 0 to 20 µM capsaicin by a 2-way ANOVA with Tukey posttest.