How is RBC production regulated?
The amount of oxygen is assessed in our kidney & liver
Enzyme that accumulates if O2 levels are low.
How does it act to increase O2?
Continuely ubiquinated in destroyed during times of sufficient oxygen
Binds as a transcription factor and upregulates genes
Proteins that are upregulated by HIF alpha and is involved in upregulation of proerythroblasts.
Erthropoietin in the kidney and liver
Transferrin and its receptor
How does Erythropoietin increase the amount of red blood cells?
JAK2/STAT5 parhway to increase stem cell differentiation into proerythroblasts
Increases maturation rate
Prevents apoptosis of hemocytoblasts
What may cause anemia?
Decreased RBC or Hb
Bone marrow damage
Kidney Damage (loss of erythropoietin)
Caused by deficiency in iron
What allows Fe++ into the cell.
Divalent Metal Transporter (DMT1)
Converts Fe2+ back to ferric state
Hephaestin or Ceruloplasmin
How much oxygen bound to Hb?
1.32 O2ml/g of Hb
What is the normal amount of Hb per 100 ml of blood in an average person.
Formula for oxygen content
oxygen capacity x % saturation
Why do RBC's perform anareobic glycolysis
To maintain a flexible membrane
Maintain Fe2+ in it's ferrous state
Prevent oxidation of Hb
How are RBC phagocytosed
In spleen or by other macrophages
Iron is recycled
Heme broken down to bilirubin
What is Polycythemia and why is it dangerous?
More oxygen carrying capacity
Blood becomes more viscous and heart must work harder to pump it.
Can be primary (vera) or secondary
What can be the mutation in Hemochromatosis?
Hepcidin Mutation (Heridtary mutation in HFE)
Blocks ferroportin to reduce intestinal uptake of iron
What is secondary polycethemia caused by?
Bone marrow is normal
Too many RBCs responding to altitude (physiological polycythemia)
What is Primary polycethemia (Polycythemia vera) caused by?
Bone marrow is making RBC when there is no need
May be caused by a mutation in the receptor thrombopoietin.
Which way does an Hb-O2 curve shift in an increased affinity for O2?
To the left
What does the Bohr effect show about the effect of CO2 or ph on a oxygen binding curve?
High C02 (which makes ph low) = left shift in affinity
Low C02 (which means pH is high) = right shift in affinity
A temperature increase has what effect on the affinity for oxygen to Hb?
Disease that exhibits the presence of large amounts of ferric iron (3+) in the heme.
Why is bound ferric iron dangerous?
Ferric iron cannot bind oxygen, this increases the affinity of oxygen in other chains so drastically that they cannot release O2.
This disease results in symptoms like anemia.
What are the four functions of blood?
Delivery of nutrients/oxygen
Removal of wastes
A bluish tint in lips, skin, extremidies.
Where is iron absorbed
70% bone marrow
What is the effect of hemochromatosis?
Iron overload associated with cardiomyopathy
Reduced transferin levels