Week 3 Hematopoietic Function Flashcards
All components of blood derive from what stem cell?
Hematopoietic stem cells (HSCs) (hemocytoblast)
What stimulates production of RBCs?
Erythropoietin (EPO)
Where is erythropoietin produced (fetal and adult)
Fetal: liver
Adult: kidneys
How does a higher elevation change RBC count and why?
It increases RBCs due to the lower oxygen level.
How does an athlete’s RBCs differ from a typical presentation?
Higher RBC count because of the oxygen demands.
What stimulates the production of Granulocytes and Macrophages?
CSFs (Colony-stimulating Factors)
1. GM-CSF - granulocyte/macrophage CSF
2. G-CSF - granulocyte CSF
3. M-CSF - macrophage CSF
interlukin-3 - multipotential CSF
What hormone stimulates platelet production?
Thrombopoietin (TPO or THPO)
What 2 organs secrete thrombopoietin?
Kidneys and Liver
What is produced by thrombopoietin that produces platelets?
Megakaryocytes
What type of feedback loop regulates platelets?
Negative feedback loop. Reduced levels promote production.
What is the job of Primary hemostasis?
Formation of platelet plug
What is the job of Secondary homeostasis?
Reinforce platelet plug with fibrin (protein mesh)
Which coagulation factors require vitamin K?
II, VII, IX, X
What food is vitamin K found in?
green leafy foods.
Is vitamin K fat-soluble or water-soluble?
Fat-soluble
What are the enzymes used in the Vitamin K cycle?
- quinone reductase
- L-Glutamyl carboxylase (for use in factors II, VII, IX, X)
- epoxide reductase (recycles vitamin K to be re-used)
Which enzyme does Warfarin block?
Epoxide reductase (recycles vitamin K to be re-used) which lowers levels THEN factors II, VII, IX, X don’t get activated.
Vitamin K dependent anti-coagulant proteins? (2)
Proteins S and C (prevent over-coagulation)
What does tPA stand for?
Tissue plasminogen activator
What does tPA convert?
Plasminogen into plasmin
What component dissolves clots?
Plasmin
What is the byproduct of plasmin after it dissolves clots?
D-dimer
What order does the intrinsic coagulation pathway function.
XII, XI, IX, then X (12, 7, 9, them 10)
What causes activation of factor VIII (8)? and what factor does it act as a co-factor for?
Separation from Von Willebrand factor. Co-factor to IXa (9a).