How does ADP activate platelets?

ADP not only causes primary aggregation of platelets but is also responsible for the secondary aggregation induced by ADP and other agonists. ADP also induces platelet shape change, secretion from storage granules, influx and intracellular mobilization of Ca2+, and inhibition of stimulated adenylyl cyclase activity.

What does adenosine diphosphate do in platelets?

Adenosine diphosphate (ADP) is an important platelet agonist that plays a role in hemostasis and pathophysiological arterial thrombosis. 1 ADP causes platelets to undergo shape change, release granule contents, and aggregate.

Does ADP inhibit platelet aggregation?

Conclusion— ADP inhibits platelet aggregation in the presence of a P2Y12 antagonist through conversion to adenosine. Inhibition occurs in PRP but not in whole blood except when adenosine uptake is inhibited.

What stimulates the release of ADP for secondary platelet aggregation?

ADP and platelet activation. Platelet activation by potent agonists such as thrombin or collagen causes the release of secondary agonists such as thromboxane A2 (TxA2) and the secretion of ADP from platelet dense granules.

How do platelets get activated?

Platelet activation is stimulated by bound platelet secretion products and local prothrombotic factors such as tissue factor. Multiple pathways can lead to platelet activation.

What stimulates platelet activation?

What inhibits platelet activation and/or aggregation?

Platelet aggregation inhibitors work in different places of the clotting cascade and prevent platelet adhesion, therefore no clot formation. Aspirin, the most commonly used antiplatelet drug changes the balance between prostacyclin (which inhibits platelet aggregation) and thromboxane (that promotes aggregation).

What chemical activates platelets?

Thrombin also promotes secondary fibrin-reinforcement of the platelet plug. Platelet activation in turn degranulates and releases factor V and fibrinogen, potentiating the coagulation cascade.

What is ADP induced platelet aggregation?

Adenosine diphosphate (ADP) is a platelet agonist that causes platelet shape change and aggregation as well as generation of thromboxane A2, another platelet agonist, through its effects on P2Y1, P2Y12, and P2X1 receptors.