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Updated: Aug 15, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
[Amiloride decreases heart susceptibility to "calcium paradox" after total ischemia]
Abstract:
It is shown that reperfusion of the postischemic heart by low-calcium solution and standard media was accompanied by a massive release of myoglobine, contracture development without cardiac contractions. Addition of amiloride (35 mmol/1) 5 min before ischemia and during low-calcium reperfusion prevents the heart damage after reintroduction of the standard-calcium media. We consider that high susceptibility of the postischemic heart to calcium paradox can be explained by activation of Na/H exchange and a decrease in the sodium gradient during low-calcium reperfusion. These findings confirm the so-called "intracellular sodium" hypothesis of the calcium paradox.
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