Thromb Haemost 1977; 38(04): 0984-0989
DOI: 10.1055/s-0038-1651916
Original Article
Schattauer GmbH

Thrombin-Stimulated Myosin Phosphorylation in Intact Platelets and its Possible Involvement Secretion

James L. Daniel
1   Specialized Center for Thrombosis Research, Temple University Medical School, Philadelphia, Pennsylvania, and the Molecular Cardiology Section, National Heart and Lung Institute, Bethesda, Maryland, U.S.A.
,
Holm Holmsen
1   Specialized Center for Thrombosis Research, Temple University Medical School, Philadelphia, Pennsylvania, and the Molecular Cardiology Section, National Heart and Lung Institute, Bethesda, Maryland, U.S.A.
,
Robert S. Adelstein
*   Molecular Cardiology Section, National Heart and Lung Institute, Bethesda, Maryland, U.S.A.
› Author Affiliations
Further Information

Publication History

Publication Date:
04 July 2018 (online)

Summary

A 20,000 dalton polypeptide, which is phosphorylated in intact platelets pre-incubated with 32P-P04, has been identified as a platelet myosin light chain. Stimulation of intact platelets with thrombin produced a 5-fold increase in the amount of radioactive phosphate incorporated into the light chain. Myosin phosphorylation preceeded acid hydrolase secretion and occurred concomitantly with adenine nucleotide secretion. These results are suggestive of participation of contractile mechanisms in platelet secretion.

 
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