银杏内酯B对血小板活化因子引起的巨噬细胞趋化及细胞骨架改变的影响

目的考察银杏内酯B(ginkgolide B，BN52021)对血小板活化因子(PAF)引起的小鼠腹腔巨噬细胞趋化反应和丝状肌动蛋白(F-actin)聚合作用的影响。方法Boyden小室法检测化合物对巨噬细胞趋化的影响；流式细胞术检测特异性标记的巨噬细胞中F-actin的变化。结果PAF可显著刺激小鼠腹腔巨噬细胞产生趋化效应，PAF受体拮抗剂BN52021(0.01 nmol·L^-1～0.1 μmol·L^-1)可明显抑制该作用。此外，在含钙缓冲液中，BN52021可显著抑制PAF引起的丝状肌动蛋白聚合。结论BN52021可能通过抑制丝状肌动蛋白的聚合作用，从而抑制PAF引起的巨噬细胞趋化，并且这种作用是钙依赖性的。表明BN52021的抗炎作用途径之一是抑制PAF诱导的趋化作用。

Effect of ginkgolide B on the platelet-activating factor induced changes of chemotaxis and cytoskeleton of macrophages

AIM: To study the inhibitory effect of ginkgolide B (BN52021) on the PAF induced changes of chemotaxis of murine peritoneal macrophages and the related polymerization of F-actin. METHODS: Chemotaxis assays were performed using a modified 48-well Boyden chamber. Actin polymerization of murine peritoneal macrophages was analyzed by flow cytometry using a specific fluorescent stain. RESULTS: Peritoneal macrophages significantly migrated toward platelet-activating factor (PAF) through a micropore filter; however, in the presence of PAF receptor antagonist BN52021 (0.01 nmol x L(-1) -0.1 micromol x L(-1)), the migration was significantly inhibited. Moreover, BN52021 inhibited the actin polymerization of murine peritoneal macrophages induced by PAF in the presence of Ca2+, but not in Ca2+ -free medium. CONCLUSION: The results suggested that preventing polymerization of F-actin may be a pathway by BN52021 to inhibit the chemotaxis of macrophages, and this effect seems to be Ca2+ dependent. The data further indicated that inhibition of PAF induced macrophage chemotaxis is an important mechanism underlying the anti-inflammatory action of BN52021.