Clot Retraction & Fibrinolysis

● Hemostasis Physiology:
• Platelet Plug Formation: https://youtu.be/zfut06No5xE
• Blood Coagulation Cascade: https://youtu.be/3LY_-c7YSjU
• Clot Retraction & Fibrinolysis: (Current video)
• Anticoagulant Factors: https://youtu.be/ja_XiXsYfbw
• Vitamin K: Biochemistry/Pharmacology: https://youtu.be/r90ptZSF6q0

● Drugs affecting Hemostasis:
• Heparin, LMWH & Fondaparinux: https://youtu.be/TacjRFCNDeI
• Warfarin (Vitamin K Antagonists): https://youtu.be/CG8FrfSxomo
• Fibrinolytics & Antifibrinolytics: https://youtu.be/IIQyw-Rkdf4
• Antiplatelet Drugs: https://youtu.be/TJp7DTMWCx0

Clot retraction occurs by interaction of actin and myosin filaments in platelets. During the process clot oozes serum. Serum is basically plasma without clotting factors. It lacks clotting factors as they are used up in clot formation. So, it cannot coagulate. Eventually the break in vessel is repaired, so clot starts to dissolve. The process starts with tissue plasminogen activator(t-PA) which activates plasminogen that was trapped in clot when clot was being formed. Thus, the inactive plasminogen is converted to active plasmin. Plasmin degrades fibrin meshwork into fibrin degradation products. This leads to dissolution of clot. Fragments of clot are cleared by phagocytes. Plasmin also prevents unnecessary clot formation as healthy sites. Its non-specific and can also degrade other clotting factors. So, its activity at healthy sites is kept under control by plasminogen activator inhibitor which inhibit plasminogen activator and α2 antiplasmin which inhibits plasmin. At clot, fibrin potentiates activity of plasminogen activator as well as prevents active plasmin from inhibitory effect of α2-antiplasmin by occupying its active site. So, at clot, plasmin activity is higher.

#NonstopHemostasis

DISCLAIMER: This video is for education purpose only. Although every effort is made to ensure accuracy of material, viewer should refer to the appropriate regulatory body/authorised websites, guidelines and other suitable sources of information as deemed relevant and applicable. In view of possibility of human error or changes in medical science, any person or organization involved in preparation of this work accepts no responsibility for any errors or omissions or results obtained from use of information in this video.

Видео Clot Retraction & Fibrinolysis канала Nonstop Neuron