Effect of 2H2O upon D-glucose metabolism in rat and human erythrocytes.

When either rat or human erythrocytes were incubated for 90-180 min in bicarbonate-buffered media prepared in 2H2O rather than 1H2O, the generation of 3HOH from D-[5-3H]glucose, the production of either 14CO2 or 14C-labelled acidic metabolites from D-[U-14C]glucose and the production of L-lactic acid from unlabelled D-glucose were decreased, to a variable extent but, in no case, by more than 30%. Hence, total substitution of 1H2O by 2H2O provides a suitable tool to study by NMR the generation of 2H-enriched L-lactic acid generated from exogenous D-[1-13C]glucose or D-[6-13C]glucose and, hence, to further explore the diabetes-induced alteration of hydrogen isotopes intermolecular transfer in the reaction catalyzed by phosphoglucoisomerase.