Sha'afi R I, Shefcyk J, Yassin R, Molski T F, Volpi M, Naccache P H, White J R, Feinstein M B, Becker E L
J Cell Biol. 1986 Apr;102(4):1459-63. doi: 10.1083/jcb.102.4.1459.
The addition of the calcium ionophore A23187 to rabbit neutrophils increases the amount of actin associated with the cytoskeleton regardless of the presence or absence of calcium in the incubation medium. In the presence of extracellular calcium, the effect of A23187 is biphasic with respect to concentration. The action of the ionophore is rapid, transient, and is inhibited by pertussis toxin, hyperosmolarity, and quinacrine. On the other hand, the addition of pertussis toxin or hyperosmolarity has small if any, effect on the rise in intracellular calcium produced by A23187. While quinacrine does not affect the fMet-Leu-Phe-induced increase in cytoskeletal actin and the polyphosphoinositide turnover, its addition inhibits completely the stimulated increase in Ca-influx produced by the same stimulus. The results presented here suggest that a rise in the intracellular concentration of free calcium is neither necessary nor sufficient for the stimulated increase in cytoskeletal-associated actin. A possible relationship between the lipid remodeling stimulated by chemoattractants and the increased cytoskeletal actin is discussed.
向兔中性粒细胞中添加钙离子载体A23187会增加与细胞骨架相关的肌动蛋白量，无论孵育培养基中是否存在钙离子。在细胞外钙离子存在的情况下，A23187的作用在浓度方面呈双相性。离子载体的作用迅速、短暂，且受到百日咳毒素、高渗和奎纳克林的抑制。另一方面，添加百日咳毒素或高渗对A23187产生的细胞内钙离子升高影响很小（如果有影响的话）。虽然奎纳克林不影响甲酰甲硫氨酸-亮氨酸-苯丙氨酸诱导的细胞骨架肌动蛋白增加和多磷酸肌醇周转，但其添加会完全抑制由相同刺激产生的钙离子内流的刺激增加。此处呈现的结果表明，细胞内游离钙离子浓度的升高对于刺激细胞骨架相关肌动蛋白增加既非必要条件也非充分条件。讨论了趋化因子刺激的脂质重塑与细胞骨架肌动蛋白增加之间的可能关系。
