Platelet aggregation:
Chapter: 20a
The process by which platelets stick to each other at the site of vascular injury, forming a platelet plug. Platelets are activated by agonists (thrombin, collagen, ADP) which activates fibrinogen receptors and allow platelets to become cross-linked by fibrinogen. Strong aggregation responses require platelets to synthesize thromboxane A2, which requires the enzyme cyclo-oxygenase. Fibrin degradation products can inhibit platelet aggregation by blocking fibrinogen receptors. Platelet aggregation is abnormal with the use of certain drugs (e.g.,aspirin, ibuprofen), and in disseminated intravascular coagulation and renal failure.
See Also: