Thromb Haemost 1991; 66(03): 350-354
DOI: 10.1055/s-0038-1646419
Review Article
Schattauer GmbH Stuttgart

Loss of Thrombin-Induced Ca2+ Mobilization in a Subpopulation of Platelets during Storage

Rob Fijnheer
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Christa H E Homburg
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Berend Hooibrink
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Martine N Boomgaard
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Dirk de Korte
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Dirk Roos
The Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
› Author Affiliations
Further Information

Publication History

Received 20 August 1990

Accepted 11 March 1991

Publication Date:
25 July 2018 (online)

Summary

Thrombin-induced changes in cytosolic free Ca2+ ([Ca2+]i) were studied in human platelets that had been stored for up to 6 days. Changes in [Ca2+]i were measured with Indo-1-loaded platelets and quantitated with two different methods: (i) measurement of the changes in total fluorescence; (ii) measurement of the [Ca2+]i changes in individual platelets in a flow cytometer, allowing the detection of non-responding platelets. The maximal concentration of [Ca2+]i after stimulation with 0.5 U of thrombin/ml decreased from 544 ± 58 nM (mean ± SEM, n = 6) on day 0, to 276 ± 9 nM on day 3 and to 203 ± 23 nM on day 6. The percentage of platelets responding to 0.5 U of thrombin/ml declined from 90 ± 2% on day 0 to 72 ± 4% on day 3, and to 47 ± 8% on day 6. Nevertheless, also the responding platelets showed a decreased rise in [Ca2+]i.

The study shows that during platelet storage a decrease in the rise in [Ca2+]i upon thrombin stimulation occurs. This decrease is partly due to the formation of a subpopulation of platelets that is completely unresponsive and partly due to a decreased responsiveness in the remainder of the platelets; it is not due to a gradual decline in [Ca2+]i rise in all platelets. This phenomenon provides new insight in the functional defect of stored platelets.