Early Ca2+ signalling events in neutrophils detected by rapid confocal laser scanning

Biochem J. 1995 Sep 1;310 ( Pt 2)(Pt 2):445-8. doi: 10.1042/bj3100445.


Characterization of early Ca2+ signalling events is crucial for understanding the mechanisms which lead to cell signalling. Rapid confocal laser scanning of Fluo3-loaded neutrophils was used to provide spatially resolved cytosolic free Ca2+ measurements from neutrophils stimulated with formyl-Met-Leu-Phe with a time resolution of 12.5 ms. Heterogeneity of the magnitude and timing of the response was observed between individual neutrophils. There was always a delay between contact with the stimulus and onset of the Ca2+ signal, with a minimum delay of 75 ms and a mean delay of 530 ms (n = 150). There was no delay in the cytosolic free Ca2+ rise induced by ionomycin. The earliest Ca2+ event detected following stimulation with formyl-Met-Leu-Phe (1 microM) was a localized rise in cytosolic free Ca2+ from a location within the cell, pointing to Ca2+ store release as the initial event for triggering whole-cell Ca2+ changes in these cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aniline Compounds
  • Calcium / blood*
  • Cytosol / metabolism
  • Fluorescent Dyes
  • Humans
  • In Vitro Techniques
  • Kinetics
  • Microscopy, Confocal / methods
  • Neutrophils / physiology*
  • Signal Transduction*
  • Time Factors
  • Xanthenes


  • Aniline Compounds
  • Fluorescent Dyes
  • Xanthenes
  • Fluo-3
  • Calcium