Figure 7.

Effects of physical stimulation of HMC-1 on whole-cell patch-clamp current (a) and intracellular Ca²⁺ activity (b) mediated by TRPV2 channels. (a) Currents were recorded at −100 mV and activated by mechanical stress (−60 cm H₂O) applied to the patch pipette, by heat (exposure to solution preheated to 53 °C), or by red laser light (at 640 nm and 48 mW). The columns represent the current in the absence (not filled) and the presence (red) of an TRPV inhibitor (20 µM SKF96365 or 10 µM Ruthenium red). In addition, the inhibitor-sensitive, TRPV2-mediated components (difference) are shown (green). The data are normalized to the current signal that can be induced by physical stimuli. The signal changes are significant based on p< 0.05. Data are extracted from Zhang et al. (2012) [38]. (b) Increase in intracellular Ca²⁺ fluorescence intensity was measure in HMC-1 cells loaded with 4 µM “Calcium Green-1AM”. TRPV2 is activated by mechanical stress (hypotonic solution (240 mOsm compared with 310 mOsm) applied to the cell suspension), by heat (exposure to solution preheated to 53 °C), or by red laser light (at 640 nm and 48 mW). The columns represent the intensities in the absence (not filled) and the presence (red) of an TRPV4 inhibitor (20 µM SKF96365). The TRPV2-mediated Ca²⁺ increase is considered to the difference (green). The data are normalized to the fluorescence signal that can be induced mechanically. The signal changes are significant based on p< 0.01, and on data from Zhang et al. (2012) [38].