[Characterization of the state of cardiac energy metabolism using NMR spectroscopy of 31P: comparison with biochemical data].

The metabolic alterations induced, in the isolated rat heart, by graded ischaemia and reperfusion, were evaluated both by 31P-NMR spectroscopy and by biochemical analysis. The relative changes in phosphorylated compound contents measured by both methods were well correlated for ATP (r = 0.94) and Pi (r = 0.88), but less for PC (r = 0.72). These results demonstrate that the data drawn from the 2 methods compare well, for the assessment of the effects of ischaemia on the isolated heart. In order to characterize the extent or energetic alterations caused by ischaemia and reperfusion from the data drawn from a single NMR spectrum various indices have been calculated. A simple index (Formula: see text) seems to this regard, as discriminative as the adenylate charge or the phosphorylation potential.