SIGNAL GENERATION AND SECRETION OF MEDIATORS IN RAT BASOPHIL LEUKEMIC CELLS

钙离子载体诱导大鼠嗜碱粒细胞分泌组胺 与肌醇水解相关的白血病(RBL-2H3)细胞 磷脂，但不随胞浆中钙离子的增加而增加。 然而，外源(Ca(2+))对分泌是必需的(J.Biol)。 化学。262：414,1987)。在释放的过程中观察到了相同的模式 花生四烯酸。在组胺释放方面也发现了相似之处。 和花生四烯酸在抗原刺激的细胞中。发布了 两者都通过霍乱毒素的治疗和 雄激素类似物的存在，并被抑制 磷酸二酯酶抑制剂IBMX为原状或透析型 细胞。尽管它们的释放可能取决于 在膜的水平上相同的信号，随后的机制 对于释放可能有分歧：花生四烯酸的释放是 使用最佳浓度的A23187比 最佳的抗原浓度，反之亦然 用来释放组胺。也是蛋白激酶C的抑制剂或 蛋白激酶耗尽(细胞长期暴露于 佛波酯)导致组胺分泌减少，但 促进花生四烯酸在细胞刺激时的释放 抗原。

Ca2+-Ionophore-induced secretion of histamine from rat basophil leukemic (RBL-2H3) cell correlated with the hydrolysis of inositol phospholipids but not with the increase in cytosol (Ca(2+)). However, external (Ca(2+)) was obligatory for secretion (J. Biol. Chem. 262:414,1987). The same pattern was observed for release of arachidonic acid. Similarities were noted in release of histamine and arachidonic acid in antigen-stimulated cells. The release of both were enhanced by treatment with cholera toxin and by the presence of andenosine analogs and were inhibited by the phosphodiesterase inhibitor IBMX in either intact or permeabilized cells. Although their release may depend on the generation of the same signals at the level of the membrane the subsequent mechanisms for release probably diverge: the release of arachidonic acid was 4 to 5 times greater with optimal concentrations of A23187 than with optimal concentrations of antigen whereas the reverse was true for release of histamine. Also inhibitors of protein kinase C or depletion of protein kinase (by prolonged exposure of cells to phorbol ester) resulted in reduced secretion of histamine but enhanced release of arachidonic acid upon stimulation of cells with antigen.