Calcium dependent inositol trisphosphate-induced calcium release in the guinea-pig taenia caeci

Biochem Biophys Res Commun. 1987 Jan 15;142(1):47-52. doi: 10.1016/0006-291x(87)90449-9.

Abstract

The properties of the Ca stores in the skinned fiber bundles of the guinea-pig taenia caeci were studied by a novel method to measure Ca released from the stores using a fluorescent Ca indicator, fura-2. It is found that the capacity of the Ca stores amounts some 170 mumoles/liter cell water. There are at least two Ca release mechanisms, Ca-induced Ca release (CICR) and Ca release induced by inositol-1,4,5-trisphosphate (IP3). Only about a half of the Ca is released by the Ca-induced Ca release, while IP3 releases most of the Ca. The rate of the IP3-induced Ca release is found to be strongly enhanced by submicromolar concentrations of Ca2+.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Benzofurans / metabolism
  • Caffeine / pharmacology
  • Calcium / metabolism*
  • Calcium / pharmacology
  • Cell Compartmentation / drug effects
  • Fura-2
  • Guinea Pigs
  • In Vitro Techniques
  • Inositol 1,4,5-Trisphosphate
  • Inositol Phosphates / pharmacology*
  • Kinetics
  • Muscle, Smooth / metabolism*
  • Spectrometry, Fluorescence
  • Sugar Phosphates / pharmacology*

Substances

  • Benzofurans
  • Inositol Phosphates
  • Sugar Phosphates
  • Caffeine
  • Inositol 1,4,5-Trisphosphate
  • Adenosine Triphosphate
  • Calcium
  • Fura-2