抗原激活的大鼠肥大细胞中磷脂酰肌醇周转、钙离子内流和组胺释放的协同刺激。

Concerted stimulation of PI-turnover, Ca2+-influx and histamine release in antigen-activated rat mast cells.

作者信息

Ishizuka Y, Nozawa Y

出版信息

Biochem Biophys Res Commun. 1983 Dec 28;117(3):710-7. doi: 10.1016/0006-291x(83)91655-8.

PMID:6199023

Abstract

Phospholipid metabolism in rat mast cells activated by antigen was examined with reference to phosphatidylinositol (PI) turnover. Upon antigen stimulation, histamine release from passively sensitized mast cells with IgE was potentiated by adding phosphatidylserine (PS). The addition of antigen to [3H]glycerol-prelabeled and sensitized mast cells induced a marked loss of radioactivity of PI and a concurrent accumulation of 1,2-diacylglycerol (DG) and phosphatidic acid (PA) within 5 to 60 sec. Furthermore, this antigen-induced PI breakdown was enhanced in the presence of Mg2+. Histamine release occurred in parallel with PI breakdown. On the other hand, the transient Ca2+ influx into mast cells, as measured by uptake of 45Ca2+, was found to occur quickly after cells were activated by antigen, which was concerted with PI breakdown. These results suggest that enhanced PI turnover may be an important step in the biochemical sequence of events leading to release of histamine, and that not only Ca2+ but also Mg2+ appears to take a part in stimulus-response coupling in rat mast cells.

摘要

参照磷脂酰肌醇（PI）周转情况，研究了抗原激活的大鼠肥大细胞中的磷脂代谢。在抗原刺激下，通过添加磷脂酰丝氨酸（PS）可增强IgE被动致敏肥大细胞释放组胺。向用[³H]甘油预标记并致敏的肥大细胞中添加抗原，可在5至60秒内导致PI放射性显著丧失，同时1,2 - 二酰基甘油（DG）和磷脂酸（PA）积累。此外，在Mg²⁺存在的情况下，这种抗原诱导的PI分解增强。组胺释放与PI分解同时发生。另一方面，通过⁴⁵Ca²⁺摄取测量发现，肥大细胞被抗原激活后，Ca²⁺迅速短暂流入，这与PI分解一致。这些结果表明，增强的PI周转可能是导致组胺释放的生化事件序列中的一个重要步骤，并且不仅Ca²⁺，Mg²⁺似乎也参与大鼠肥大细胞的刺激 - 反应偶联。