P-31 NUCLEAR MAGNETIC-RESONANCE INVESTIGATION OF INTRACELLULAR ENVIRONMENT IN HUMAN NORMAL AND SICKLE-CELL BLOOD

  • 1 January 1979
    • journal article
    • research article
    • Vol. 54  (1) , 196-209
Abstract
Intracellular pH and 2,3-diphosphoglycerate [2,3-DPG] concentration in sickle cell anemia and normal human blood samples were measured by 31P NMR spectroscopy. To monitor the concentrations of various internal phosphorylated metabolites of intact red blood cells, heparinized blood samples were used and were incubated at 37.degree. C with 5.6% CO2, 25% O2 and 69.4% N2. The 31P chemical shifts of phosphorylated compounds such as 2,3-DPG, ATP and Pi depend on pH. By using an appropriate calibration curve, the intracellular pH of intact erythrocytes can be obtained. The intracellular pH values in fresh sickle cell blood and normal blood were 7.14 and 7.29, respectively. The whole-blood pH, as measured by a standard pH meter, was 7.54 for both types of blood. The initial concentration of 2,3-DPG in sickle cell blood was about 30% higher but was depleted much faster during incubation than that in normal blood. The difference in intracellular pH between these 2 types of blood samples remained constant during incubation, even after depletion of 2,3-DPG. There are differences in intracellular environment between normal and sickle cell blood. 31P NMR spectroscopy provides a fast, direct, continuous and noninvasive way to monitor the intracellular environment of intact erythrocytes.