Mechanisms for Ischemia/Reperfusion Injury: Application of 23Na Magnetic Resonance Spectroscopy
Intracellular sodium concentration ([Na+]i) of myocardium dramatically increases during ischemia and rapidly returns after reperfusion. [Na+]i kinetics during ischemia/reper-fusion is coupled with those of other important ions such as Ca2+ and K+. Na+ movement of intact perfused heart can be easily detected by 23Na nuclear magnetic resonance spectroscopy (MRS) combined with a shift reagent. Furthermore, the sequential [Na+]i measurement is possible due to the nucleus’ abundance in living tissue and high NMR sensitivity. Thus, 23Na-MRS has been considered to be very valuable informative method in the research of ischemia/reperfusion injury. We have applied 23Na-MRS to elucidate the mechanisms for [Na+]i kinetics during ischemia/reperfusion and its role in injury. This technique combined with quantitative method provides understanding of underlying mechanism for the alteration of ion homeostasis during ischemia/reperfusion as well as [Na+]i movement.
Key wordsintracellular Na+ concentration ion homeostasis Na+ kinetics shift reagent
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