PlateletAmyloidPrecursorProteinPathway

The amyloid -beta peptide (Ab), a proteolytic fragment of amyloid precursor protein (APP), is the major componenet of senile plaques, the hallmark of alzhemier’s disease. Platelets contain both APP and Ab and probably contribute greater than 90% of circulating APP. The soluble APP is the major inhibitor of coagulation factors IXa and XIa, and platelet aggregation. Agonists such as ADP, thrombin, epinephrine and collagen activate the release of APP and plasminogen activator inhibitor I (an important regulator of coagulation) from platelet storage granules. These important molecules released from platelets are key regulators of hemostasis, the physiologic arrest of hemorrhage at site of vascular leakage.

Contributor: Joseph Chuang, PhD

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