Release of Ca 2+ from a non-mitochondrial store site in peritoneal macrophages treated with saponin by inositol 1,4,5-trisphosphate

Masato Hirata, E. Suematsu, T. Hashimoto

Research output: Contribution to journalArticle

112 Citations (Scopus)

Abstract

The effects of inositol 1,4,5-trisphosphate, prepared from human erythrocyte ghosts, on Ca 2+ release from intracellular store sites were studied in saponin-treated guinea pig peritoneal macrophages. Micromolar concentrations of inositol 1,4,5-trisphosphate released Ca 2+ within 1 min from store sites which had accumulated Ca 2+ in the presence of 10 mM-NaN 3 . In the presence of 10 mM-NaN 3 , the Ca 2+ accumulated in the presence of oxalate was seen in the endoplasmic reticulum of saponin-treated macrophages by electron microscopy, indicating that the site of Ca 2+ released by inositol 1,4,5-trisphophate may be endoplasmic reticulum-like membranes. When the concentrations of free Ca 2+ were over 3.5x10 -6 M, the release of Ca 2+ by this agent was inhibited. This inhibition may be due to either the higher concentration of extra-vesicular free Ca 2+ or the larger accumulation of Ca 2+ into the store site or perhaps both effects. MgCl 2 also had an inhibitory effect on the Ca 2+ release. Inositol 1,4,5-trisphosphate also released Ca 2+ from cardiac sarcoplasmic reticulum, but not from erythrocyte inside-out vesicles.

Original languageEnglish
Pages (from-to)229-236
Number of pages8
JournalBiochemical Journal
Volume223
Issue number1
DOIs
Publication statusPublished - Jan 1 1984

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Release of Ca <sup>2+</sup> from a non-mitochondrial store site in peritoneal macrophages treated with saponin by inositol 1,4,5-trisphosphate'. Together they form a unique fingerprint.

  • Cite this