Temporal and spatial resolution of Ca2+ release and influx in human neutrophils using a novel confocal laser scanning mode.
Confocal laser scanning demonstrated that stimulation of neutrophils with the surface receptor agonist, f-met-leu-phe, resulted in the release of stored Ca2+ from a single site. From reconstructions of neutrophils stained with acridine orange, it was shown that the central Ca2+ release site was always close to the nucleus, and correlated with a site which stained with DiOC(6)3. Elevated Ca2+ was locally restricted to within 1 micron of this site. Release of Ca2+ by this pathway was accompanied by the influx of Ca2+, less than 1 second after store release. In each neutrophil, the Ca2+ store release component preceded the Ca2+ influx, and their spatial separation suggested communication between the Ca2+ store and the plasma membrane by a messenger. The (distance)2 of the release site from the plasma membrane was correlated to the time between Ca2+ release and influx, consistent with the diffusion of a messenger from the storage site signalling Ca2+ influx.
Pettit
E J
EJ
Department of Surgery, University of Wales College of Medicine, Heath Park, Cardiff, United Kingdom.
Hallett
M B
MB
D000165:Acridine Orange; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D002232:Carbocyanines; D002451:Cell Compartmentation; D005456:Fluorescent Dyes; D006801:Humans; D007834:Lasers; D018613:Microscopy, Confocal / Q000379:methods*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure*; D015398:Signal Transduction; D013194:Staining and Labeling / Q000379:methods; D013997:Time Factors
D002232:Carbocyanines; D005456:Fluorescent Dyes; C007392:3,3'-dihexyl-2,2'-oxacarbocyanine; D009240:N-Formylmethionine Leucyl-Phenylalanine; D000165:Acridine Orange; D002118:Calcium