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Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry
Published on: October 28, 2014
Rapidly exchanging Ca2+ stores of non-muscle cells
P Volpe1, T Pozzan, J Meldolesi
1Department of Physiology and Biophysics, University of Texas Medical Branch, Galveston 77550.
Abstract:
The rapid and transient redistribution of calcium from intracellular stores is a key event of cell activation. The nature and molecular composition of intracellular Ca2+ stores of non-muscle cells are the object of intense investigation. In this paper, we review: (a) the experimental evidence in favor of the existence of intracellular, membrane-bound compartments specialized for uptake, storage and release of calcium, (b) the main protein components of rapidly exchanging Ca2+ stores, i.e. Ca2+ pump, intralumenal Ca2+ binding proteins (calsequestrin, calreticulin, etc.) and Ca2+ channels sensitive to either inositol 1,4,5-trisphosphate or Ca2+, caffeine and ryanodine, and (c) the relationship between Ca2+ stores and the endoplasmic reticulum.
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