Relationship between [Ca2+] changes in nucleus and cytosol.
The free calcium concentration in nucleus ([Ca2+]n) and in cytoplasm ([Ca2+]c) of single cells were estimated by confocal laser microscopy using the Ca(2+)-indicator Indo-1. It is shown that in various cell types a nucleo-cytosolic Ca(2+)-gradient is present at rest and during stimulation. The direction and the extent of the nucleo-cytosolic Ca(2+)-gradient may vary with the cell type, differentiation status, phosphorylation conditions and also with the type of agonist. Evidence is given for the role of extra- and intranuclear storage sites as well as for Ca(2+)-influx. Finally potential artefactual interference with the measurements is discussed.
Himpens
B
B
Physiological Laboratory, K. U. Leuven, Gasthuisberg, Belgium.
De Smedt
H
H
Casteels
R
R
D000818:Animals; D001693:Biological Transport, Active; D002118:Calcium / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism*; D003587:Cytomegalovirus / Q000502:physiology; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D018613:Microscopy, Confocal; D010766:Phosphorylation
D002118:Calcium