ANP 1105 Lecture Notes - Lecture 11: Liver Disease, Haemophilia, Cirrhosis

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: Jacqueline Carnegie

Document Summary

Process by which the body stops bleeding upon injury and maintains blood in the fluid state with vessel integrity. Contain purple staining granules that contain clotting factors and enzymes. 250 000 - 500 000 platelets /ul blood. Vasonconstritcion of vessel in response to damage. Triggers - damage, chemicals from endothelial cells and platelets. Purpose - valuable bc a strongly constricted artery can significantly reduce blood loss. 20-30 min allow time for next steps: platelet plug formation. Usu platelets do not stick to each other or to endothelial lining. No and pgi2 (prostacyclin) produced by endothelial cells; inhibits platelet aggregation in undamaged tissue. Exposure of collagen stimulates platelets to swell , become spiky and sticky. Adhere to exposed collagen (von willebrand factor) - degranulation. Enhances vascular spasm and aggregation: primary hemostasis. Can easily be dislodged from the vessel wall: platelet function: Provide negatively charged surface for factor x and prothrombin activation.