ACQUIRED GRANULAR POOL DEFECT IN STORED PLATELETS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 57  (2) , 203-208
Abstract
Platelets stored as concentrates (PC) for 72 h at 22.degree. C develop a functional defect. Alterations in adenine nucleotides of [human] platelets affected platelet function. Adenine nucleotide content of platelets was measured before and after storage and a decrease of 27.1 .+-. 1.7% (mean .+-. SE) in ATP and 39.1 .+-. 2.6% in ADP were found in 34 PC stored with final volume of 50 ml. In 11 PC with 30 ml volume, ATP and ADP decreased by 39.4 .+-. 3.2% and 49.4 .+-. 2.1%, respectively. The mean ATP to ADP ratio of stored platelets was significantly higher than of fresh platelets in both groups, suggesting a relatively greater decrease in granular than metabolic pool nucleotides. Levels of low affinity platelet factor 4 measured by radioimmunoassay in plasma increased from 0.86 .+-. 0.08 .mu.g/ml in the fresh PC to 8.59 .+-. 0.39 .mu.g/ml in stored PC, indicating a concomitant .alpha.-granular secretion. Labeling of metabolic pool with 14C-adenine revealed a mean decrease in the adenylate energy charge of 2.0 .+-. 0.4% in 12 of 16 stored PC, with a lower ATP and higher hypoxanthine labeling in stored as compared to fresh platelets. Stored platelets develop an acquired defect in both dense and .alpha. granules and in their ability to maintain ATP homeostasis.