Intrinsic Pathway.pdf

Intrinsic Pathway Introduction: this is called intrinsic because it is activated by factors already present within the blood. This is a slow pathway Starts with activation of hegman factor(xii) by exposed collagen. Factor 12 hence activates 6 plasma thromboplastin (F 11) and fac...

Intrinsic Pathway Introduction: this is called intrinsic because it is activated by factors already present within the blood. This is a slow pathway Starts with activation of hegman factor(xii) by exposed collagen. Factor 12 hence activates 6 plasma thromboplastin (F 11) and factor 11 activates factor 9. Factor 9 and 8 works in conjunction 5 to amplify clotting process, the combined action results in the activation of factor 10 4 FACTORS INVOLVED ORDERLY 3. Factor 12 2. Factor 11 1. Factor 9. Factor 8. Factor 10 Extrinsic Pathway Introduction: This is called extrinsic pathway because it’s activated by factors external to blood. This is a faster pathway This starts when Thromboplastine(F 3)enters the blood from a damaged tissue. The presence of 3 factor 3 in blood hence activates factor 7. Factor 3 and factor 7 work in conjunction to activate 2 factor 10. 1 FACTORS INVOLVED. Factor 3. Factor 7. Factor 10 Both the intrinsic and extrinsic pathway converge to form a common pathway that lead to blood coagulation. CONVERGENCE In both pathways factor 10 is formed and this factor plays the central role in initiating the common pathway. Firstly the factor 10 in combination with factor 5 forms the prothrombin activator/ prothrombinase. This prothrombin activator converts prothrombin to thrombin with 5 help of calcium then thrombin converts fibrinogen to fibrin. 4 REQUIREMENTS FOR COMMON PATHWAY 3. Factor 10 & factor 5 2. Prothrombinase 1. Prothrombin. Thrombin. Fibrinogen. Fibrin here's the list of blood clotting factors: 1. Factor I (Fibrinogen) 2. Factor II (Prothrombin) 3. Factor III (Tissue Factor) 4. Factor IV (Calcium) 5. Factor V (Labile Factor, Proaccelerin) 6. Factor VI (Not a clotting factor) 7. Factor VII (Stable Factor, Proconvertin) 8. Factor VIII (Antihemophilic Factor A) 9. Factor IX (Antihemophilic Factor B, Christmas Factor) 10. Factor X (Stuart-Prower Factor) 11. Factor XI (Plasma Thromboplastin Antecedent, PTA) 12. Factor XII (Hageman Factor) 13. Factor XIII (Fibrin Stabilizing Factor)