Role of Cytoplasmic pH for Stimulus-Induced CA2+ Mobilization in Human Platelets

  • Winfried Siffert
  • Peter Scheid
  • Jan W. N. Akkerman
Conference paper
Part of the NATO ASI Series book series (NSSA, volume 135)


Stimulation of human platelets by thrombin resulted in cytoplasmic alkalinization due to activation of Na+/H+ exchange. Inhibition of this Na+/H+ exchange suppressed the thrombin-induced Ca2+ mobilization. Artificial cytoplasmic alkalinization, on the other hand, markedly enhanced the stimulus-induced rises in the cytosolic free Ca2+ concentration. It is concluded that activation of Na+/H+ exchange is needed for Ca2+ mobilization and thus constitutes an essential step in platelet activation.


Human Platelet Inositol Trisphosphate Platelet Suspension Dependent Calcium Channel Cytoplasmic Free Calcium 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Winfried Siffert
    • 1
  • Peter Scheid
    • 1
  • Jan W. N. Akkerman
    • 1
    • 2
  1. 1.Inst. für Physiol.Ruhr-UniversitätBochumGermany
  2. 2.Department of HaematologyUniversity HospitalThe Netherlands

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