Fig. 2.

Regulation of collagen-mediated dense granule secretion and TxA₂ production by CXCR4. Washed platelets (2 × 10⁸/mL^− 1) were pre-treated with vehicle control or inhibitors; (A, Ci) 100 nM AMD3100 (CXCR4) and (B, Cii) 10 μg/mL^− 1 11G8 (CXCR7) or IgG₁ control in the presence of 10 μg/mL^− 1 IV.3 and stimulated with increasing concentrations of collagen. ATP release from dense granules (A, B) was assessed by lumi-aggregometry, while TxA₂ production (C) was monitored by a TxB₂ ELISA using releasates generated from samples in A–B. Representative secretion traces (A–Bi) and peak ATP release values (nmoL ATP/10⁸ platelets, A–Bii) are shown. Data are mean ± SEM, n = 4, *P < 0.05 vs. vehicle, Two-way ANOVA with Bonferroni post-hoc analysis.