Maitotoxin-Induced Phosphoinositide Hydrolysis Is Dependent on Extracellular but Not Intracellular Ca2+ in Human Astrocytoma Cells

The Japanese Journal of Pharmacology

Toshiko Yaginuma¹  Norimichi Nakahata¹  Yasushi Ohizumi¹ 

[1] Department of Pharmaceutical Molecular Biology, Graduate School of Pharmaceutical Sciences, Tohoku University

关键词: Maitotoxin;    Phosphoinositide hydrolysis;    Ca2+;   

DOI  :  10.1254/jjp.81.240

学科分类：药理学

来源: Nihon Yakuri Gakkai Henshuubu / Japanese Pharmacological Society

【 摘 要 】

References(15)Cited-By(4)Since maitotoxin, a potent marine toxin, is known to cause not only Ca2+ influx but also phosphoinositide hydrolysis, we investigated the Ca2+ dependency of maitotoxin-induced phosphoinositide hydrolysis in 1321N1 human astrocytoma cells. Maitotoxin elicited inositol 1, 4, 5-trisphosphate accumulation in a time-dependent manner. In [3H]inositol-labeled cells, maitotoxin stimulated phosphoinositide hydrolysis in an extracellular Ca2+-dependent manner. Maitotoxin also caused an intracellular Ca2+ elevation, which was abolished by an intracellular Ca2+ chelater BAPTA-AM. Interestingly, maitotoxin still caused phosphoinositide hydrolysis in the BAPTA-AM-treated cells. These results indicate that maitotoxin-induced phosphoinositide hydrolysis is dependent on extracellular but not intracellular Ca2+ in 1321N1 human astrocytoma cells.

【 授权许可】

Unknown