Roles of Ca2+ on the inositol 1,4,5-trisphosphate-induced release of Ca2+ from saponin-permeabilized single cells of the porcine coronary artery

Comp Biochem Physiol A Comp Physiol. 1985;82(3):645-9. doi: 10.1016/0300-9629(85)90446-3.

Abstract

The release of Ca2+ from the intracellular store site, as induced by inositol 1,4,5-trisphosphate, was studied in relation to free Ca2+ concentrations or amounts of stored Ca2+ in smooth muscle cells. The maximal Ca2+ release induced by inositol 1,4,5-trisphosphate was observed when the amount of Ca2+ in the store site was about 50% of the maximal capacity of the Ca2+ storage, and when the extravesicular free Ca2+ concentration was less than 1.5 X 10(-6) M. The Ca2+ release induced by inositol 1,4,5-trisphosphate was accelerated by ATP and 5'-adenylylimidodiphosphate (AMPPNP), but not by ADP and AMP. This inositol 1,4,5-trisphosphate-induced Ca2+ release appeared to be specific for intracellular Ca2+ store sites (mainly sarcoplasmic reticulum), and this Ca2+ release was not apparent in the sarcolemmal fraction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Diphosphate / pharmacology
  • Adenosine Monophosphate / pharmacology
  • Adenosine Triphosphate / pharmacology
  • Adenylyl Imidodiphosphate / pharmacology
  • Animals
  • Calcium / metabolism*
  • Calcium / pharmacology
  • Cell Membrane Permeability / drug effects
  • Coronary Vessels / drug effects
  • Coronary Vessels / metabolism*
  • In Vitro Techniques
  • Inositol 1,4,5-Trisphosphate
  • Inositol Phosphates / pharmacology*
  • Kinetics
  • Saponins / pharmacology*
  • Sugar Phosphates / pharmacology*
  • Swine

Substances

  • Inositol Phosphates
  • Saponins
  • Sugar Phosphates
  • Adenylyl Imidodiphosphate
  • Adenosine Monophosphate
  • Adenosine Diphosphate
  • Inositol 1,4,5-Trisphosphate
  • Adenosine Triphosphate
  • Calcium