Term
| Inhibitors of Platelet Aggregation |
|
Definition
1. ADPase
2. PGI2 (Prostaglandin I2)
3. NO
Secreted by endothelial cells |
|
|
Term
| Inhibitors of coagulation factors |
|
Definition
|
|
Term
|
Definition
Activated by thrombin-thrombomodulin complex on endothelial cells to become aPC.
Inactivates Factors Va and VIIIa.
Protein S is cofactor |
|
|
Term
|
Definition
Inhibits Factors Xa and Thrombin.
Activated by Heparin. |
|
|
Term
| Sequence of Protein C activation |
|
Definition
| 1. Thrombomodulin on endothelial cells form complex with Thrombin. 2. Thrombin-thrombomodulin complex activates Protein C to aPC. 3. Protein S forms factor with aPC. 4. Protein S-aPC complex goes on to inactivate Factors Va and VIIIa. |
|
|
Term
| Congenital Antithrombin Deficiency |
|
Definition
| People who have this lack antithrombin, so body is unable to inactivate Factors Xa and thrombin effectively. More susceptible to thrombosis. |
|
|
Term
|
Definition
Used to break down clots. All convert plasminogen to plasmin to break down fibrin.
1. Urokinase
2. Streptokinase
3. tPA (most commonly used) |
|
|
Term
|
Definition
| Not enough platelets in blood, leads to uncontrolled bleeding. Clinical manifestation: Platelet count under 100,000/uL. |
|
|
Term
|
Definition
| Derived from megakaryocytes. Released from bone marrow and circulate in blood for 7-10 days. |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Platelet storage location |
|
Definition
| 30% of platelets kept in spleen. |
|
|
Term
|
Definition
| Glycoprotein hormone produced in the liver, bone marrow stroma, kidney, and smooth muscle. Stimulates platelet formation. |
|
|
Term
| Negative feedback regulation of TPO |
|
Definition
| Platelets have receptors for TPO, increased platelet number will decrease TPO synthesis. |
|
|
Term
| Causes of Thrombocytopenia |
|
Definition
1. Low TPO production (liver cirrhosis)
2. Immune destruction
3. Sequestration (hepatomegaly or splenomegaly) |
|
|
Term
|
Definition
Too many platelets in blood (>600,000/uL)
1. Reactive Thrombocytosis (happens after surgery or infection)
2. Essential Thrombocytosis (only platelet count goes up)
3. Chronic myelocytic leukemia (CML)
4. Polycythemia vera (PV) |
|
|
Term
| Platelet Derived Growth Factor (PGDF) |
|
Definition
| Secreted by platelets, stimulates smooth muscle cell growth. |
|
|
Term
|
Definition
1. vWF
2. Tissue factor (complex with factor VIIa)
Secreted by endothelial cells. |
|
|
Term
| Antithrombotic Endothelial Cell Secretions |
|
Definition
1. ADPase
2. PGI2 (Prostaglandin I2)
3. NO
4. Heparin Sulfate
5. Thrombomodulin |
|
|
Term
|
Definition
1. Synthesized by endothelial cells and megakaryocytes.
2. Bridge between platelets and collagen.
3. Carrier protein for factor VIII (stabilizes half life) |
|
|
Term
| Mechanism of vWF binding to collagen and platelets |
|
Definition
| 1. vWF is a large protein containing many multimers that are capable of unfolding. 2. Upon shear force and flow, these multimers unfold and are able to bind to collagen and platelet GPIb receptors. |
|
|
Term
|
Definition
Most common hereditary bleeding disorder caused by a deficiency in vWF, affects 1-2% of population.
Type I: most mild form, easy bruising.
Type II: intermediate, abnormal vWF
Type III: Complete vWF deficiency, extreme bleeding. |
|
|
Term
|
Definition
| Binds fibrinogen between 2 platelets in platelet aggregation phase of primary hemostasis. |
|
|
