In platelets, the term "alpha granules" is used to describe granules containing several growth factors (such as insulin-like growth factor 1 and platelet-derived growth factor ) and other clotting proteins (such as thrombospondin and fibronectin.) A 250 ml bag of newly collected platelets. ... A granule is a small grain. ... Insulin-like growth factor 1 (IGF-1) is a polypeptide protein hormone similar in molecular structure to insulin. ... Platelet-derived growth factor (PDGF) is one of the numerous proteins that regulate cell growth and division. ... Coagulation is the thickening or congealing of any liquid into solid clots. ... Thrombospondins (TSP) are secreted proteins with the ability to inhibit angiogenesis. ... Fibronectin is a high molecular weight glycoprotein containing about 5% carbohydrate that binds to receptor proteins that span the cells membrane, called integrins. ...

A deficiency of alpha granules is known as grey platelet syndrome.

See also

• Dense granule

External links

• Harrison P, Cramer E (1993). "Platelet alpha-granules.". Blood Rev 7 (1): 52-62. PMID 8467233.