SIGNAL GENERATION AND SECRETION OF MEDIATORS IN RAT BASOPHIL LEUKEMIC CELLS

离子载体诱导大鼠嗜碱粒细胞分泌组胺 白血病(RBL-2H3)细胞与蛋白水解酶的关系 肌醇磷脂不随胞浆Ca(2+)的增加而增加 ((Ca(2+)虽然增加(Ca(2+))，但对分泌是必需的 (J.Boil Chem.262：414 1987)。同样的模式也被观察到 释放花生四烯酸。此外，释放这两个人 组胺和花生四烯酸被激活剂增强 蛋白激酶C在这种情况下的释放是 与(Ca(2+))的升高相关。释放的程度 因此，组胺和花生四烯酸单独作用于离子载体可能 受到蛋白激酶C激活程度的限制 而不是(Ca(2+))增加的幅度。随后的 释放机制可能会有很大不同：释放 花生四烯酸是最优的4到5倍 A23187的浓度比最佳浓度的 蛋白激酶激活剂不存在或存在时的抗原 C.组胺的释放不是这样的，对于组胺来说， 需要离子载体和蛋白激酶C的激活剂 与最佳抗原浓度诱导的释放相匹配 独自一人。

Ionophore-induced secretion of histamine from rat basophil leukemic (RBL-2H3) cells correlated with the hydrolysis of inositol phospholipids but not with the increase in cytosol Ca(2+) ((Ca(2+))) although increased (Ca(2+))) was obligatory for secretion (J. Boil Chem. 262:414 1987). The same pattern was observed for release for arachidonic acid. Moreover, the release of both histamine and arachidonic acid was enhance by activators of protein kinase C and in this circumstance the release was correlated with the increase in (Ca(2+))). The extent of release of histamine and arachidonic acid to ionophore alone, therefore, may be limited by the extent of activation of protein kinase C rather than by the extent of increase in (Ca(2+))). The subsequent mechanisms of release may well differ: the release of arachidonic acid was 4 to 5 times greater with optimal concentrations of A23187 than with optimal concentrations of antigen in the absence or presence of activators of protein kinase C. This was not true for release of histamine for which both ionophore and an activator of protein kinase C were required to match the release induced by optimal concentrations of antigen alone.