Localization of surface vWF on resting and stimulated platelets.
We used immunoelectron microscopic localization techniques to investigate whether platelets stimulated by ADP or ristocetin in the plasma milieu bind von Willebrand factor (vWF) to their surfaces. We found by both peroxidase- and ferritin-based methods that unstimulated platelets lack vWF on their surfaces, whereas platelets that are stimulated with ADP or ristocetin have vWF associated with their surfaces. The specificity of the findings was confirmed by absorption studies using severe von Willebrand disease (vWD) and hemophilic plasmas. The anti-vWF antibodies were blocked by incubation with hemophilic plasma but not by incubation with severe vWD plasma. Thus, in the plasma environment, in the presence of fibrinogen, vWF becomes associated with the platelet surface subsequent to stimulation with ADP or ristocetin.
Rand
J H
JH
Department of Medicine, Mount Sinai School of Medicine, New York.
Gordon
R E
RE
Uson
R R
RR
Potter
B J
BJ
D000244:Adenosine Diphosphate / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D008854:Microscopy, Electron; D010974:Platelet Aggregation / Q000187:drug effects; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012016:Reference Values; D012310:Ristocetin / Q000494:pharmacology; D014841:von Willebrand Factor / Q000378:metabolism*
D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D014841:von Willebrand Factor; C028254:von Willebrand factor receptor; D012310:Ristocetin; D000244:Adenosine Diphosphate