Properties of intra- and intercellular Ca(2+)-wave propagation elicited by mechanical stimulation in cultured RPE cells.
Membrane deformation induced by a mechanical stimulus increases the [Ca2+]i in cultured retinal pigment epithelial (RPE) cells, and in many other cell types. In this study, confocal microscopy and Ca(2+)-measurements using the fluorescent dye fluo-3 were used to measure the spatiotemporal characteristics of the Ca(2+)-wave propagation during a mechanical stimulation in Long Evans (LE) RPE cells or dystrophic Royal College of Surgeons (RCS) RPE cells. Ca2+ signals were recorded in the mechanically stimulated cell and in the neighboring cells. A regenerative Ca(2+)-wave with a decreasing rate of propagation was found in the stimulated cells. The rate of propagation was significantly slower in RCS-RPE cells compared to LE-RPE cells. Incubation with thapsigargin significantly lowered the propagation rate in both LE- and RCS-RPE cells. The amplitude of the [Ca2+]i-rise in the nucleus and cytoplasm was differentially modulated by protein kinase C in RCS-RPE cells, but not in LE-RPE cells. It is concluded that RCS-RPE cells have intracellular Ca(2+)-regulating properties which are different from those of LE-RPE cells.
Stalmans
P
P
Laboratory of Physiology, KULeuven, Belgium.
Himpens
B
B
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D003593:Cytoplasm / Q000378:metabolism; D007424:Intracellular Fluid / Q000378:metabolism; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D020318:Rats, Long-Evans; D013347:Subcellular Fractions
D002118:Calcium