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Platelet‐derived SDF‐1α (CXCL12) mediates inflammatory and regenerative mechanisms. The present study characterizes the effect of SDF‐1α ligation in platelets. SDF‐1α (0–100 μM) dose and time dependently caused internalization of its receptor CXCR4 (28.9±1.6 vs. 16.1±1.9 in SDF‐1α‐treated platelets), coupled to the surface externalization of CXCR7 (65.5±8 vs. 162.8±27.6 following SDF‐1α treatment), both in vitro and in vivo. This was inhibited in the presence of AMD3100 (100 μM), CXCR4 blocking and vesicular transport inhibitors (brefeldin A, 10 μM; rapamycin, 100 nM). SDF‐1α/CXCR‐4‐mediated CXCR7 translocation was significantly reduced by inhibitors of ERK1/2‐(U0126‐10 μM) and cyclophilinA (CyPA)‐(NIM811‐10 μM) by 28 and 46%, respectively. Further, SDF‐1α‐induced downstream phosphorylation of Erk1/2 led to CyPA‐dependent ubiquitination of CXCR7, which is essential for its …