Abstract
23Na nuclear magnetic resonance (NMR) spectroscopy was utilized to measure intracellular Na+ in perfused ferret hearts exposed to the shift reagent dysprosium triethylenetetramine-hexa-acetic acid [Dy(TTHA)3-]. The intracellular Na+ signal was small under normal perfusion conditions; resolution was enhanced by using a Jump-Return NMR pulse protocol. During 20 min of total global ischemia at 30°C, intracellular Na+ concentration ([Na+](i)) increased steadily to a peak value fivefold greater than control. [Na+](i) declined monotonically back to control levels within 9 min of reperfusion. In contrast, the mean contractile pressure only recovered to 54% of control levels. Thus major alterations in Na+ homeostasis occur during severe ischemia. [Na+] recovers rapidly during reperfusion and is therefore dissociated from the lingering postischemic depression of contractile function known as 'stunning'.
Original language | English (US) |
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Pages (from-to) | H1767-H1773 |
Journal | American Journal of Physiology - Heart and Circulatory Physiology |
Volume | 259 |
Issue number | 6 28-6 |
DOIs | |
State | Published - 1990 |
Externally published | Yes |
Keywords
- cardiac function
- nuclear magnetic resonance spectroscopy
- stunned myocardium
ASJC Scopus subject areas
- Physiology
- Cardiology and Cardiovascular Medicine
- Physiology (medical)