High resolution proton NMR studies of perfused rat hearts

High resolution 1H NMR spectra of perfused rat hearts have been obtained under normoxic, ischemic and hypoxic conditions. Several myocardial metabolites including taurine, carnitine, lactate and tissue glycerides are detected in the 1H NMR spectra. Changes in oxygen availability induce perturbations in the levels of some metabolites, in particular, lactate. Experiments with fasted rats and with substrate-free perfusion suggest that the glycerides detected in 1H spectra are metabolically mobilizable but have a slow rate of turnover. These results demonstrate that utility of 1H NMR in monitoring myocardial metabolism.