Figure 7. Effect of jasplakinolide on non-capacitative cation entry in human platelets.

A-D, platelets were pretreated for 30 min at 37 °C with 10 μm JP (C and D; n = 6) or the vehicle (ethanol; A and B; n = 6). Cells were stimulated with PMA (1 μm) in HBS containing 1 mm Sr²⁺. B and D show, respectively, confocal images of F-actin labelled with FITC-conjugated phalloidin in control or JP-treated human platelets. Scale bars represent 1 μm. E-H, cells were pretreated at 37 °C with 10 μm JP (F and H) or the vehicle (ethanol; E and G) for 30 min. The platelets were then treated with TG (1 μm) and IONO (50 nM) in Ca²⁺-free HBS (100 μm EGTA added) and 3 min later SrCl₂ (final concentration, 300 μm; E and F) or CaCl₂ (final concentration 300 μm; G and H) was added followed by thrombin (10 U ml⁻¹; n = 7).