Thrombin-induced platelet membrane glycoprotein IIb and IIIa complex formation. An electron microscope study. Academic Article uri icon

Overview

abstract

  • The topographic relationships of platelet membrane glycoprotein IIb and glycoprotein IIIa have been studied in stimulated and unstimulated human platelets using immunoelectron microscopy. An indirect approach with ferritin-conjugated goat anti-rabbit gamma-globulin was used to localize the rabbit antibody to glycoprotein IIIa. The second ultrastructural label was keyhole limpet hemocyanin conjugated directly to antibody to glycoprotein IIb. Using the double labels, it was demonstrated that glycoprotein IIb and glycoprotein IIIa were distributed randomly in the unstimulated platelet membrane. After platelet stimulation with thrombin, large clusters of glycoprotein IIb-glycoprotein IIIa complexes were formed. No complex formation between glycoprotein Ib and glycoprotein IIb was observed in control experiments. These observations suggest that thrombin stimulation initiates the specific glycoprotein IIb-glycoprotein IIIa macromolecular complex formation on the platelet surface, which may act as the active fibrinogen-binding site required for normal platelet aggregation.

publication date

  • October 1, 1981

Research

keywords

  • Blood Platelets
  • Glycoproteins
  • Membrane Proteins
  • Thrombin

Identity

PubMed Central ID

  • PMC2186487

Scopus Document Identifier

  • 0019494293

Digital Object Identifier (DOI)

  • 10.1084/jem.154.4.1058

PubMed ID

  • 6457076

Additional Document Info

volume

  • 154

issue

  • 4