Figure 5. Effects of compounds 1–4 on PKC activation and intracellular calcium mobilization.

(A) Washed human platelets were incubated with DMSO or each compound (5 μM) at 37 °C for 10 min, and were stimulated with U46619 (2 μM, left) or thrombin (0.05 U/mL, right) for another 1 min. Phospho-MARCKS in the platelet lysates was detected using western blotting (cropped images from full-length gels). (B,C) Fura-2-loaded human platelets were incubated with DMSO (D), compound 1 (white box), 2 (light gray box), 3 (dark gray box), and 4 (black box) at 37 °C for 10 min in the presence of 1 mM extracellular Ca²⁺, followed by the addition of U46619 (B, 2 μM) or thrombin (C, 0.05 U/mL) to trigger the increase in [Ca²⁺]_i. The data represent the means ± SEM of three independent experiments performed in triplicate. ^*p < 0.05 vs. U46619 (B) or Th (C) alone.