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W Kuhl

Publications and source records attributed to W Kuhl.

82 records · Page 5Linked to original sources

Platelet glycolysis in platelet storage. II. Levels and turnover of metabolic intermediates.

The metabolism of freshly collected platelets and platelets stored for three or four days at room temperature has been investigated. The levels of glycolytic intermediates were measured in platelets before and after incubation for 15 minutes in a buffered aerobic medium. Platelet intermediates were relatively well maintained, and levels of intermediates that were partially depleted, such as ATP, were restored toward normal after short term incubation even after storage for four days. Incorporation of 32PO4 into fresh and stored platelets during incubation in aerobic buffered medium was also studied. The incorporation pattern was only very modestly influenced by storage. These studies suggest that changes in glycolytic capacity do not play a major role in the loss of viability of platelets during storage at room temperature.

Adenosine Triphosphate↗

Platelet glycolysis in platelet storage. IV. The effect of supplemental glucose and adenine.

Platelet concentrates were prepared from blood collected in CPD, CPD-A1, and CPD-A3. CPD-A1 contains 1.25 times as much glucose as does CPD, and sufficient adenine to provide a final concentration of 0.25 mM; CPD-A3 contains twice as much glucose as does CPD, and sufficient adenine to provide a final concentration of 0.5 mM. The consumption of glucose and the production of lactate and pyruvate in the platelet concentrates during room temperature storage was not influenced by glucose or adenine concentration. There was no difference in the rates of fall of the pH of platelets collected in the three preservatives. However, the number of contaminating white blood cells had a significant effect on these parameters. It is suggested that minimizing the number of contaminating white blood cells in platelet preparations may prove to be an important factor in platelet preservation.

Adenine↗

Volume control of erythrocytes during storage. The role of mannitol.

When red cells are stored as suspensions in artificial preservative solutions such as those consisting of saline, adenine, and glucose, increased hemolysis of the red cells occurs in vitro, a phenomenon that is readily prevented by the addition of mannitol. The mechanism by which mannitol prevents hemolysis is unknown. The authors have examined the possibility that mannitol prevents hemolysis by prevention of osmotic swelling of red cells that might otherwise increase their volume beyond their critical hemolytic volume. Storage in artificial media does, indeed, result in swelling of the red cells, which is prevented by mannitol and is increased by the addition of nystatin, an agent that greatly increases the sodium-potassium permeability of the cells. Swelling and hemolysis are correlated at different concentrations of mannitol, but the correlation breaks down when the case of nystatin-treated cells is considered; even with marked swelling, there is relatively little hemolysis. Moreover, increasing the volume of the stored red cells acutely by osmotic means results in relatively little additional hemolysis. These findings make it appear unlikely that simple osmotic lysis is the cause of hemolysis in stored cells. Some other stabilizing effect of mannitol that may or may not be related to its osmotic effect must play a role.

Blood Preservation↗