Non-destructive measurement of metabolites and tissue pH in the kidney by 31P nuclear magnetic resonance.

Phosphorus nuclear magnetic resonance (31P NMR) can be used as a non-destructive method for the simultaneous observation of the major phosphate-containing metabolites (ATP, ADP, nucleotide monophosphate, Pi, sugar phosphate) and intracellular pH in isolated rat kidney. The time course of changes in these metabolites and in cellular pH in the ischaemic kidney are examined at two temperatures and in the presence of different flushing media. ATP is rapidly depleted while the pH change is slower and shows biphasic behaviour. Pi production and total nucleotide (ATP and ADP) depletion also occur on the same time-scale as the tissue acidification. The relation of these observations to tissue viability is discussed and the possibility of extending the measurements to human organs is considered.