Platelets

Platelets are small, anucleate, disc-shaped blood cells derived from bone marrow megakaryocytes which serve several critical roles in normal haemostasis and participate in both health and disease.

Keywords: platelets; receptors; thrombocytopenia; bleeding; coagulation

Figure 1. Participation of platelets in clot formation following blood vessel injury. Platelets become activated and accumulate at the site of vascular endothelial injury. This aggregation of activated platelets (platelet plug) stops the escape of blood from the circulation and supports the formation of fibrin which stabilizes the platelet plug.
Figure 2. (a) Electronmicrograph of a quiescent platelet (magnification ×30 000) showing platelet constituents. DB, dense body; G, glycogen; MT, mitochondria; CM, cell membrane; OCS, open canalicular system and DTS, dense tubular system. (b) An activated platelet demonstrating the collagen-induced shape changes (magnification ×30 000). (c) Collagen-induced platelet aggregation (magnification×30 000).
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 Further Reading
    book Bussel JB and Cines DB (1995) "Immune thrombocytopenic purpura, neonatal autoimmune thrombocytopenia, and post-transfusion purpura". In: Hoffman R, Benz EJ, Shattil SJ et al. (eds) Hematology: Basic Principles and Practice, 2nd edn, pp. 1849–1869. New York: Churchill Livingstone.
    Cines DB, Bussel JB, McMillan RB and Zehnder JL (2004) Congenital and acquired thrombocytopedia. Hematology/the Education Program of the American Society of Hematology. American Society of Hematology. Education Program 1: 390–406.
    book Diz-Kucukkaya R, Gushiken FC and Lopez JA (2007) "Thrombocytopenia". In: Lichtman MA, Beutler E, Kipps TJ et al. (eds) Williams' Hematology, 7th edn, pp. 1749–1783. New York: McGraw-Hill Medical Publishing Division.
    book Gewirtz AM and Schick B (1994) "Megakaryocytopoiesis". In: Colman RW, Hirsh J, Marder VJ and Salzman EW (eds) Hemostasis and Thrombosis: Basic Principles of Clinical Practice, 3rd edn, pp. 353–396. Philadelphia: Lippincott.
    book Parise LV, Smyth SS, Shet AS and Coller BS (2007) "Platelet morphology, biochemistry, and function". In: Lichtman MA, Beutler E, Kipps TJ et al. (eds) Williams' Hematology, 7th edn, pp. 1587–1663. New York: McGraw-Hill Medical Publishing Division.
    book Plow EF and Ginsberg MH (1995) "Molecular basis of platelet function". In: Hoffman R, Benz EJ, Shatill SJ et al. (eds) Hematology: Basic Principles and Practice, 2nd edn, pp. 1524–1535. New York: Churchill Livingstone.
    Postlethwaite AE and Chiang TM (2007) Platelet contributions to pathogenesis of systemic sclerosis. Current Opinion Rheumatology 19: 574–579.
    book Shulman NR and Jordan JVJ (1987) "Platelet immunology". In: Colman RW, Hirsh J, Marder VJ and Salman EW (eds) Hemostasis and Thrombosis: Basic Principles and Clinical Practice, pp. 452–529. Philadelphia: Lippincott.
    book Sullivan KA and Kipps TJ (2007) "Human leukocyte and platelet antigens". In: Lichtman MA, Beutler E, Kipps TJ et al. (eds) Williams’ Hematology, 7th edn, pp. 2137–2150. New York: McGraw-Hill Medical Publishing Division.
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How to Cite close
Chiang, Thomas M, and Dietcher, Steven R(Jul 2008) Platelets. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0001221.pub2]