Concerted Oxygen-17/Phosphorus-31 Magnetic Resonance Spectroscopy: A Novel Approach for In Vivo Correlation of Oxygen Consumption and Phosphate Metabolism
After discoveries that initiated the understanding of the structural and functional organization of the cell (A. Claude, C. de Duve and G. Palade, Nobel Prize 1974) and the definitive description of the fine structure of mitochondria (Palade et al., 1948–1952), in vitro studies of oxidative phosphorylation (Lehninger et al., 1950; B. Chance et al., 1955, 1985;) yielded valuable information concerning the effects of inhibitors and uncoupling agents (Pietrobon et al., 1987). Recently, a discussion of a paradigm for aging and degenerative diseases (D.C. Wallace, 1992) emphasized the possible relation of mitochondrial DNA mutations with defects in oxidative phosphorylation (OXPHOS). In order to obtain reliable correlations between oxygen consumption and ATP formation it is necessary to avoid, on one side, the uncertainties due to in vitro measurements and, on the other, the variations in metabolism due to other factors than mutants or uncoupling agents. We report here preliminary results of the first attempt to make virtually simultaneous in vivo 17O and 31P magnetic resonance spectroscopy (MRS) measurements.