Episode 5- CLOTTING YO Flashcards
_________ is designed to ensure that there is no major leakage of blood following injury and consists of a complex system of proteins and enzymes.
Hemostasis
What are the two extremes if there is an abnormality in the homeostasis proteins?
Bleeding (not enough clotting) & Thrombosis (too much clotting)
A single megakaryocyte can generate around _____ platelets, of which _______ are pooled in the spleen (as sort of a “reserve”).
3000!….20-30%
A normal level of platelets is between ____________ per cubic millimeter of blood.
250,000 - 400,000
Like RBCs, platelets have no nucleus or organelles, but contain many _______.
granules
Platelets possess an average life span of _______ and hence must be continuously produced by the bone marrow.
5-20 days
What is the most important layer and sublayer of the vessel we will discuss in clotting?
the connective tissue layer of the tunica intima
When discussing the anatomy of the capillary: Tunica intima only contains _________ and small amounts of _______.
endothelial cells…..collagen
What are the three phases of homeostasis?
1.Vascular Spasm (vasoconstrictive phase) 2.Platelet Plug Formation 3.Blood Clotting
What is the main event of the first phase of vessel homeostasis and what ate the two ways this phase is accomplished?
The vasoconstrictive phase/vascular spasm phase occurs when smooth muscle directly around the injury contracts…it is triggered by 1.the direct injury and 2.the SymNS
Phase 2 of homeostasis: ___________. Characterized by the aggregation of platelets. Platelets stick to exposed ______, swell, and form spiked process. Platelet _____ are effective in preventing blood loss due to ______ injuries.
collagen….plugs….small
HOW DO THOSE platelets stick to collagen to form a plug?! Platelets stick to the exposed collagen of damaged endothelium (or an artificial surface) via _____ receptors.
GPIa receptors (GP = glycoprotein)
HOW DO THOSE platelets stick?!?! ______________ is a protein found in plasma, platelets and the walls of blood vessels – via _____ receptors, it specifically causes platelets to attach firmly to and spread across the damaged endothelial surface.
von Willebrand’s Factor (vWF)…..GPIb receptors
What are the three secretions of the platelets during plug formation? What do theses secretions bind to?
1.ADP (adensosine diphosphate) 2.Thromboxane A2 (a prostaglandin) 3.Serotonin…..They bind to OTHER PLATELETS!
Aggregation of platelets occurs as a consequence of another platelet glycoprotein receptor called _______ onto which _______ and other macromolecules bind tightly.
GPIIb/IIIa….fibrinogen
Most of the clotting factors are present in the circulation as __________ (_______) to prevent unwanted clotting.
inactive proteins (zymogens)
Factors __, __, __, and __ are vitamin K-dependent clotting factors.
II,VII,IX,X…2,7,9,10….Two,Seven,Nine, Ten.
Clotting Factor: I…. Name and Origin Plez
I…Fibrinogen…Liver
Clotting Factor: II…. Name and Origin Plez
II…ProThrombin…Liver
Clotting Factor: III… Name and Origin Plez
III…Tissue Factor or ThromboPlastin….PeriVascular Tissue
Clotting Factor: IV….Name and Origin Plez
IV…Calcium…Plasma
Clotting Factor: V Name and Origin Plez
V…ProAccelerin (Labile Factor)…Liver
Clotting Factor: VII Name and Origin Plez
VII….ProConvertin (Stable Factor)…Liver
Clotting Factor: VIII Name and Origin Plez
VIII….AntiHemophilic factor A, Antihemophilic globulin…Liver
Clotting Factor: IX Name and Origin Plez
IX…AntiHemophilic factor B, Plasma thromboplastin compontent, CHRISTMAS factor!!!…Liver
Clotting Factor: X Name and Origin Plez
X….Stuart-Prower factor(weird)….Liver
Clotting Factor: XI Name and Origin Plez
XI…Plasma thromboplastin antecedent, Hemophilia C, Rosenthal Syndrome…Liver
Clotting Factor: XII Name and Origin Plez
XII….Hageman Factor….Liver,Platelets
Clotting Factor: XIII Name and Origin Plez
XIII….Fibrin stabilizing factor, Laki-Lorand factor….Platelets, Plasma
In addition to coagulation factors, the plasma contains several ____________ that rapidly inactivate coagulation factors that escape the site of injury.
protease inhibitors
What are the three examples of the “anti-coagulant” system that balances coagulation?
1.Thrombo-Modulin 2.Anti-thrombin III (aka Anti-Thrombin) 3.Heparin cofactor II
ThromboModulin: A glycoprotein present on endothelial cells that combines with _______.
thrombin
The thrombomodulin-thrombin complex activates _________.
PROTEIN C
Protein C and its cofactor, _________, degrade factors __ and __
PROTEIN S….V and VIII.
___________ is a glycoprotein produced by the liver that binds to and subsequently inhibits factor X and thrombin
Antithrombin III
____________ is a plasma protein synthesized by the liver and inhibits thrombin.
Heparin cofactor II
The Fibrolytic system is initiated by the enzyme _______ which is synthesized from an inactive plasma protein synthesized by the liver called ________.
PLASMIN……..PLASMINOGEN