Erythrocyte Physiology Flashcards
What does HIF alpha do if O2 levels are low?
accumulates –> binds w/ HIF beta in the nucleus –> increases scrip of genes including EPO to MAKE MORE RBCS
How much O2 can 1 g of Hb carry?
1.34 mL O2/ g Hb
What is primary polycythemia?
bone marrow is making RBC when there is no need to (not normal)
may be due to mutation in receptor for thrombopoietin
What does Hypoxia inducible factor (HIFalpha) do if there is sufficient oxygen delivered to kidney?
ubiquinated and destroyed
What causes hereditary hemochromatosis?
missense mutation in the gene for hepcidin –> cant inhibit ferroportin to stop absorbing iron
What happens to the heart in hemochromatosis?
cardiomyopathy
A left shift in the Hb-O2 curve would do what?
When would this happen?
increase affinity of Hb for 02
low CO2
high pH
What does erythropoietin do?
increases stem cell differentiation into proerythroblasts
increases maturation rate of committed erythrocytic precursors
to make more RBCs!
What happens in polycythemia?
too many rbcs –> increased o2 capacity and content
blood becomes thicker
heart has to work harder to pump blood
What is secondary polycythemia?
bone marrow normal
responding to low o2 levels
could be because of high altitude, lung/heart disease
What happens to the heart in anemia?
increased workload
What happens to Met-hemoglobin
contains Fe3+ –> o2 can’t bind –> body acts like anemic
Other chains w/ iron in ferrous state have increased affinity for o2, but can’t let it go –> tissues don’t get enough o2
What organ is very important in telling the body to make more rbc to get tissues more oxygen?
kidney
What is the format of oxygen capacity?
mL O2/dL blood
What happens in a RIGHT shift of Hb-o2 curve?
When would this occur?
decreases affinity of Hb for O2 low pH Increase in CO2 increased temp increased 2,3 BPG
