Subcellular calcium shifts in ischemia and reperfusion

Subcellular calcium shifts and pathological calcification are observed under conditions of myocardial ischemia and/or reperfusion cell injury and represent the more severe manifestations of abnormal calcium (Ca2+) homeostasis. The use of specialized techniques for measurement of intracellular electrolytes such as electron probe x-ray microanalysis and the use of the fluorescent Ca2+ indicator, fura 2, are providing new insights into regulation of intracellular Ca2+ and the role of altered Ca2+ homeostasis in the pathogenesis of myocardial cell injury. During the progression of myocardial cell injury, investigations indicate that increased intracellular Ca2+ develops in association with other manifestations of membrane injury, including other electrolyte alterations, altered cell volume regulation, and altered membrane phospholipids.