Regulation of store-operated Ca2+ entry in pulmonary artery smooth muscle cells

Stuart P. McElroy, Robert M. Drummond, Alison M. Gurney

    Research output: Contribution to journalArticlepeer-review

    Abstract

    Store-operated Ca2+ entry (SOCE) is an important mechanism for Ca2+ influx in smooth muscle cells; however the activation and regulation of this influx pathway are incompletely understood. In the present study we have examined the effect of several protein kinases in regulating SOCE in pulmonary artery smooth muscle cells (PASMCs) of the rat. Inhibition of protein kinase C with chelerythrine (3 μM) potentiated SOCE by 47 ± 2%, while the tyrosine kinase inhibitors genistein (100 μM) and tyrphostin 23 (100 μM) caused a significant reduction in SOCE of 55 ± 9% and 43 ± 7%, respectively. It has been proposed that Ca2+-insensitive phospholipase A2 (iPLA2) is involved in the activation of SOCE in many different cell types. The iPLA2 inhibitor, bromoenol lactone had no effect on SOCE, suggesting that this mechanism was not involved in the activation of the pathway. The calmodulin antagonists, calmidazolium (CMZ) (10 μM) and W-7 (10 μM) appeared to potentiate SOCE in PASMCs. Further investigation established that CMZ was actually activating a Ca2+ influx pathway that was independent of the filling state of the sarcoplasmic reticulum. The CMZ-activated Ca2+ influx was blocked by Gd3+ (10 μM), but unaffected by 2-APB (75 μM), indicating a pharmacological profile distinct from the classical SOCE pathway. © 2009 Elsevier Ltd. All rights reserved.
    Original languageEnglish
    Pages (from-to)99-106
    Number of pages7
    JournalCell calcium
    Volume46
    Issue number2
    DOIs
    Publication statusPublished - Aug 2009

    Keywords

    • Ca2+ independent phospholipase A2
    • Calmodulin
    • Protein kinase C
    • Pulmonary artery
    • Smooth muscle
    • Store-operated Ca2+ entry
    • Tyrosine kinase

    Fingerprint

    Dive into the research topics of 'Regulation of store-operated Ca2+ entry in pulmonary artery smooth muscle cells'. Together they form a unique fingerprint.

    Cite this