Measured and predicted time courses of pH and metabolic intermediates in PAGGGM-stored RBCs.

<p><i>Panel A</i>: Time courses of intracellular pH at 37°C (measured values; ▪) and at 4°C (estimated values; •); fitted value used in the model (–). <i>Panel B</i>: ATP and 2,3-BPG were measured by CE-TOFMS (<i>left column</i>) and predicted by the mathematical model (<i>right column</i>) in which free-form (<i>solid black</i>) and total amount (<i>broken black</i>) of metabolites are shown separately. Since intracellular ATP and 2,3-bisphophoglycerate (2,3-BPG) are known to bind to hemoglobin and band 3 membrane protein <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0071060#pone.0071060-Kinoshita1" target="_blank">[8]</a>, in our model, free-form metabolite represents its amount in plasma, and total amount of metabolite represents the sum of metabolites (free-form) in plasma and their binding to the proteins. <i>Panel C</i>: Measured or predicted time courses of intermediates in glycolysis (G6P, F1,6-BP, DHAP, PYR, LAC), non-oxidative pentose phosphate pathway (R5P, RU5P), and purine salvage pathway (PRPP, intracellular HX, and ADE), respectively. pH and capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) data are expressed as means ± SD of 6 separate experiments. An asterisk indicates that a two-sided <i>p</i>-value is <0.01 versus the Day 0 values.