Quantification of [Ca2+]i in perfused hearts. Critical evaluation of the 5F-BAPTA and nuclear magnetic resonance method as applied to the study of ischemia and reperfusion.

Author:

Marban E1,Kitakaze M1,Koretsune Y1,Yue D T1,Chacko V P1,Pike M M1

Affiliation:

1. Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland.

Abstract

Calcium has been implicated as a mediator of cell injury in ischemia and reperfusion, but direct measurements of Ca2+ are required to refine this idea. We used nuclear magnetic resonance spectroscopy and the Ca2+ indicator 5F-BAPTA to measure [Ca2+]i in perfused ferret hearts. Several lines of evidence are presented to show that loading with the acetoxymethyl ester of 5F-BAPTA is not significantly complicated by accumulation of partially de-esterified metabolites, compartmentalization into mitochondria, or disproportionate uptake into endothelial cells. During 20 minutes of total global ischemia at 30 degrees C, time-averaged [Ca2+]i increased significantly, reaching peak values roughly three times control at 15-20 minutes. Reperfusion resulted in a persistent elevation of [Ca2+]i during the first 5 minutes, but not afterward. Although the nonlinear response of 5F-BAPTA to [Ca2+] leads to underestimation of the true time-averaged [Ca2+]i, the measured alterations of intracellular Ca2+ homeostasis during ischemia are large compared with the likely errors in quantification. Phosphorus nuclear magnetic resonance spectroscopy of 5F-BAPTA-loaded hearts reveals changes during ischemia similar to those recorded previously in hearts not containing a Ca2+ indicator. Developed pressure recovers to only 50% of control values during reflow, indicating that the presence of 5F-BAPTA in the cytosol does not protect against stunning, at least when the extracellular calcium concentration has been raised to 8 mM. We conclude that 5F-BAPTA provides useful measurements that reveal that time-averaged [Ca2+]i rises during ischemia and returns to control levels soon after reperfusion.

Publisher

Ovid Technologies (Wolters Kluwer Health)

Subject

Cardiology and Cardiovascular Medicine,Physiology

Reference72 articles.

1. Jennings RB: Calcium ions in ischemia in Opie LH (ed): Calcium Antagonists and Cardiovascular Disease. New York Raven Press 1984 pp 85-95

2. The role of calcium in ischemic myocardial injury;Murphy JG;Circ Res,1987

3. Calcium-mediated damage during post-ischaemic reperfusion

4. Defense Strategies Against Hypoxia and Hypothermia

5. Mandel LJ Eaton DC: Cell Calcium and the Control of Membrane Transport. Society of General Physiologists New York Rockefeller University Press 1986 vol 42

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