Dopamine Potentiation of Calcium Ionophore, A-23187-Induced Platelet Aggregation

Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 407)


Dopamine (DA) is widely studied neurotransmitter and has been implicated in several diseases. Although the effects of DA on human or rabbit platelet function have been reported (Braunsein et al., 1977), little is known about the role of DA in platelet aggregation. More recently DA1 and DA2 receptors, which couple with the guanine nucleotide binding proteins (G-proteins) have also been identified on platelets (Watson and Arkinstall, 1994). In our recent studies, we have shown that synergistic action of different agonists, when added together in subthreshold concentrations, plays a trivial role in the activation of platelets. The best known examples are ADP and collagen, thrombin and ADP, epinephrine and ADP and 5-HT and epinephrine (Heemskerk and Sage, 1994; Shah and Saeed, 1995).


Platelet Aggregation Tyrosine Phosphorylation Platelet Rich Plasma Human Platelet Calcium Ionophore 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Berridge, M.J., (1993) Inositol triphospahate and calcium signalling. Nature, 361, 315–325.PubMedCrossRefGoogle Scholar
  2. Brass, L.F., Hoscie, J.A., and Manning, D.R., 1993, Signaling through G proteins and G protein-coupled receptors during platelet activation. Thromb. Haemost. 70(1), 217–223.PubMedGoogle Scholar
  3. Clark, E.A., and Bruggs, J.S., 1993, Tyrosine phosphorylation in platelets. Potential roles in intracellular signal transduction. Trends Cardiovasc. Med., 3: 218–227.PubMedCrossRefGoogle Scholar
  4. Heemskerk, J.W.M., and Sage, O., 1994, Calcium signalling in platelets and other cells. Platelets, 5: 295–316.PubMedCrossRefGoogle Scholar
  5. Negrescu, E.V., deQuintava, K.L., and Seiss, W., 1995, Platelet shape change induced by thrombin receptor activation. J. Biol. Chem., 270: 1057–1061.PubMedCrossRefGoogle Scholar
  6. Shah, B.H., and Milligan, G., 1994, The gonadotrophin releasing hormone receptor of 1aT3-1 cells regulates cellular levels of both of the phosphoinositidase C-linked G-proteins, Gqa and Glla. Mol. Pharmacol., 46: 1–7.PubMedGoogle Scholar
  7. Shah, B.H., McEwan, D.J., and Milligan, G., 1995, Gonadotrophin releasing hormone receptor agonist-mediated downregulation of Gq/G11 (pertussis toxin-insensitive) G-proteins in aT3-1 gonadotroph cells reflects increased G protein turnover but not alterations in mRNA levels. Proc. Natl. Acad. Sci., 92: 1886–1890.PubMedCrossRefGoogle Scholar
  8. Shah, B.H., and Saeed, S.A., (1995) Phosphatidylinositol 3-kinase inhibitor, wortmannin, inhibits 5-hydroxytryp-tamine-mediated potentiation of platelet aggregation induced by epinephrine. Res. Comm. Mol. Path. Pharmacol., 89(2): 157–164.Google Scholar
  9. Takayama, H., Nakamura, T., Yanagi, S., Taniguchi, T., Nakamura, S., and Yamamura, H., 1991, Ionophore A23187-induced protein tyrosine phosphorylation of human platelets. Possible synergy between Ca2+ mobilization and protein kinase C activation. Biochem. Biophys. Res. Comm., 174: 922–927.PubMedCrossRefGoogle Scholar
  10. Thomason, P.A., James, S.R., Casey, P.J., and Downes, C.P., 1994, AG-protein β γ-subunit-responsive phosphoinositidase 3-kinase activity in human platelets cytosol. J. Biol. Chem., 269, 16525–16528.PubMedGoogle Scholar
  11. Torti, M., Grouch, M.F., and Lapetina, E.G., 1992, Epinephrine induced association of pp60src with Gi alpha in human platelets. Biochem. Biophys. Res. Commun., 186(1): 440–447.PubMedCrossRefGoogle Scholar
  12. Ui, M., Okada, T., Hazeki, K., and jazeki, O., 1995, Wortmannin as a unique probe for an intracellular signalling protein, phosphoinositide 3-kinase. Trends Biochem. Sci., 20: 303–307.PubMedCrossRefGoogle Scholar
  13. Vosatl, J.G., Jackson, W. L., and Shulman, N.R., 1991, Cytosolic and stored calcium antagonistically control tyrosine phosphorylation of specific platelet proteins. J. Biol. Chem., 266: 16911–16916.Google Scholar
  14. Watson, S., and Arkinstall, S., 1994, In: The G-protein linked receptors: Facts Book, Academic Press Ltd., pp: 42, 172.Google Scholar

Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  1. 1.Department of Physiology and PharmacologyThe Aga Khan UniversityKarachiPakistan

Personalised recommendations