Preservation of red blood cells with purines and nucleosides. II. Uptake and utilization of purines and nucleosides by stored red blood cells.
The uptake of adenine, guanine, guanosine and inosine by stored red cells was investigated in whole blood and red cell resuspensions at initial concentrations of 0.25, 0.5 and 0.75 mM for adenine and 0.5 mM for the other additives using a rapid ion-exchange chromatographic microanalysis of purines and nucleosides in plasma and whole blood. Increasing adenine concentrations from 0.25 to 0.75 mM in blood elevated the adenine uptake from 0.3 up to 0.8 mmol/l red cells during 2 hours after collecting blood. The intra-/extracellular distribution ratio changed from 1 : 1.3 to 1: 1.7. Some 2 hours after withdrawing blood into CPD--solution with purines and nucleosides the uptake of adenine and guanine resulted in 40 per cent and 70 per cent respectively and of guanosine and inosine in 80 and 90 per cent respectively. The replacement of plasma by a resuspending solution gave the same uptake rates for purines and nucleosides. The nucleosides were rapidly split to purines and R-1-P and disappeared from blood during one week. Adenine and guanine were utilized to 80 to 90 per cent only after 3 weeks. During the same period the utilization of guanine was smaller by 40 per cent than that of adenine due to the different activity of the purine nucleoside phosphorylase for these substrates. The plasma of all analyzed blood samples contained hypoxanthine and inosine, but guanine and guanosine were detected only in those samples to which one of them was added. After 3 weeks of storage the highest concentration of hypoxanthine was found in CPD-AI blood with 600 microM in plasma and the highest concentration of synthesized inosine in CPD-AG blood with a concentration of 100 microM in plasma. Three ways of utilization of purines by stored red cells were discussed : the synthesis of nucleotide monophosphates, the formation of nucleosides, and the deamination. The portions of these ways change during storage. The most effective concentrations of adenine and guanosine in stored blood seems to be 0.25 and 0.5 mM respectively. The full utilization of the nucleoside requires the addition of inorganic phosphate.
D000225:Adenine / Q000097:blood; D001793:Blood Preservation / Q000379:methods*; D004912:Erythrocytes / Q000378:metabolism*; D006147:Guanine / Q000097:blood; D006151:Guanosine / Q000097:blood; D006801:Humans; D007042:Hypoxanthines / Q000097:blood; D007288:Inosine / Q000097:blood; D009705:Nucleosides / Q000097:blood*; D011687:Purines / Q000097:blood*; D013696:Temperature
D007042:Hypoxanthines; D009705:Nucleosides; D011687:Purines; D006151:Guanosine; D007288:Inosine; D006147:Guanine; D000225:Adenine