VASCULAR/PLATELET RESPONSED

    Cards (13)

    • Prostacyclin:
      • Inhibits platelet aggregation
      • Induces vasodilation
    • Adenosine:
      • Induces vasodilation
    • Thrombomodulin:
      • Inactivates thrombin
      • Enhances anticoagulant activity of protein C
      • Protein C inactivates factor 1 and 7
    • Heparan Sulphate:
      • Enhances activity of antithrombin 3
    • Tissue plasminogen activity:
      • Converts plasminogen to plasmin
    • Von Willebrand factor:
      • Required for platelet adhesion
    • 13 Hydroxyoctadecadienoic acid:
      • Inhibits platelet adhesion
    • Physiologic Response (VCTF):
      • Vasoconstriction is a neurogenic response
      • Collagen exposure causes adherence of platelets to the site of injury and activates the contact phase of coagulation
      • Tissue thromboplastin release activates the extrinsic pathway
      • Fibrinolysis involves the release of tPA to avoid excessive coagulation
    • Platelet Adhesion:
      • Platelets adhere to collagen, fibrinonection, and basement membrane
      • Collagen Type 1 and 2, synthesized by smooth muscle in deep regions of blood vessel walls, promote platelet adhesion, aggregation, and release reaction
      • Platelets adhere to collagen via plasma VIII:vWF and platelets Glycoprotein 1b
    • 13 HODE:
      • From endothelial cells
      • Inhibits platelet adhesion
    • 12 HETE:
      • From cytosol of platelets
      • Promotes platelet adhesion
    • Platelet Release Reaction (Relationship):
      • Release of platelet granules from alpha granules and dense granules
      • Stimulated by collagen, thrombin, epinephrine, and thromboxane A2
    • Platelet Shape Change:
      • Contraction of microfilaments due to ADP release
      • Involves calcium and thrombostenin, the major contractile protein
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