title: [The physiology of primary hemostasis].
abstract: Primary haemostasis, on the same grounds as coagulation and fibrinolysis, is one of the three main stages of haemostasis. It involves mainly the vascular endothelium and the blood platelets. An endothelial lesion will uncover thrombogenic structures-mainly microfibrils and collagen-to which the platelets will adhere. The latter will then undergo a complete morphological transformation, from a discoid shape to a structure provided with pseudopods. This transformation is accompanied by a biological explosion, which affects in the first place the metabolism of prostaglandins and of cyclic AMP. There occurs also a release of the contents of the platelet granules. The final phase of platelet activation consists in their aggregation, which is reversible in a first time and irreversible afterwards. On the other hand, the activated platelets can also trigger the process of coagulation, which demonstrates the narrow relationship between the various stages of haemostasis.
authors.forename: L
authors.initials: L
authors.lastname: Verstraeten
authors.forename: P
authors.initials: P
authors.lastname: François
authors.forename: J P
authors.initials: JP
authors.lastname: Dinant
mesh_terms: D000818:Animals; D006487:Hemostasis / Q000502:physiology*; D006801:Humans
vernacular_title: Physiologie de l'hémostase primaire.