These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Cytoplasmic pH dependency of Na+/H+ exchange in human platelets activated with thrombin, arachidonic acid, A23187 and TPA.
    Author: Ogawa A, Ishikawa Y, Sasakawa S.
    Journal: Thromb Res; 1989 Sep 15; 55(6):683-93. PubMed ID: 2551067.
    Abstract:
    The cytoplasmic pH (pHc) of human platelets was lowered to 6.8-7.2 by treatment with various doses of nigericin (K+/H+ ionophore), then these platelets were stimulated with thrombin, arachidonic acid (AA), A23187 or 12-o-tetradecanoylphorbol-13-acetate (TPA), to monitor the pHc changes using a pH-sensitive fluorescent dye, BCECF. The pHc increased with the stimulation in an amiloride-sensitive manner only when the resting-pHc was lower than a certain value (pHc 6.99 for thrombin-stimulation, 6.95 for AA, 7.04 for A23187 and 6.95 for TPA, n = 3). At a higher resting-pHc, the pHc decreased. Similar observations were found using platelets acid-loaded by Na-acetate treatment. These results suggest that stimulation-induced activation of the Na+/H+ exchanger depends on cytoplasmic H+ concentration, and it can function properly only when the resting-pHc is lower than about pHc 7.
    [Abstract] [Full Text] [Related] [New Search]