Shear-induced platelet aggregation.
Two platelet mechanisms contribute to haemostasis and thrombosis. (1) Compounds such as thrombin activate glycoprotein IIb/IIIa; fibrinogen is the ligand. The cyclooxygenase pathway is involved and so this process is aspirin sensitive. (2) Shearing forces alone activate a different domain on glycoprotein IIb/IIIa; von Willebrand's factor is the ligand. This process is probably non-enzymatic and is aspirin insensitive. The prevention of shear-induced platelet activation may prove to be more rewarding therapeutically than inhibition of aspirin sensitive pathways.
O'Brien
J R
JR
Central Laboratory, St Mary's Hospital, Portsmouth, Hampshire, UK.
D001775:Blood Circulation; D001780:Blood Coagulation Tests; D001809:Blood Viscosity; D005340:Fibrinogen / Q000378:metabolism; D006440:Hemofiltration / Q000379:methods; D006801:Humans; D039421:Integrin alpha2; D008562:Membrane Glycoproteins / Q000097:blood; D015539:Platelet Activation / Q000502:physiology*; D010974:Platelet Aggregation / Q000502:physiology*; D013915:Thrombasthenia / Q000097:blood; D014842:von Willebrand Diseases / Q000097:blood / Q000503:physiopathology*; D014841:von Willebrand Factor / Q000032:analysis
C056564:ITGA2B protein, human; D039421:Integrin alpha2; D008562:Membrane Glycoproteins; C040580:glycoprotein GP III; D014841:von Willebrand Factor; D005340:Fibrinogen