RBC Metabolism Flashcards
What is the key marker for intravascular hemolysis?
hemoglobin
What is the key marker for extravascular hemolysis?
bilirubin
What protein can reduce hemoglobin? What does this enzyme use as a reducing equivalent?
Methemoglobin reductase
NADH
What protein in RBCs keep sulfhydryl groups reduced?
glutathione
Does a high or low pH inhibit hexokinase and PFK?
low
What is the substrate for the energy clutch?
1,3-bisphosphoglycerate
What is the intermediate of the energy clutch?
2,3-bisPhosphoglycerate
What is the end product of the energy clutch?
3-phosphoglycerate
Does a low or high pH inhibit the synthesis of 2,3-BPG?
low = inhibits
What does pyruvate kinase deficiency cause?
hemolytic anemia
What are the two mechanisms by which HIF1α is active in cancer cells?
- increases txn of glucose transporters
2. decreases activity of PDH
What attacks cells during PNH? Which cells?
complement
RBCs, granulocytes, platelets
Which direction does potassium move when a red cell lyses?
potassium = out
calcium = in
Does the energy clutch happen is the pH drops or rises?
drops
What are the two regulated steps of glycolysis in RBCs?
hexokinase
PFK1
Does an acidic pH inhibit or promote glycolysis?
inhibit
Is 2,3-BPG synthesis inhibited at high or low pH?
low pH
Deficiency in what two enzymes can cause a hemolytic anemia?
pyruvate kinase
G6PDase
What is the mechanism of inheritance for G6PDase deficiency?
X-linked recessive
Expression of what tx factor is upregulated in neoplastic cells? What is the function of this txn factor?
HIF-1α
promote anaerobic metabolism
Does AIP of PCT produce photo sensitivity?
PCT
According to Schmidt, defects in RBC metabolism can produce extravascular or intravascular hemolysis?
both
What metabolite is produced in excess by tumor cells? Where is this metabolite shunted?
lactate
Cori cycle
What protein can oxidize iron from Fe2+ to Fe3+?
Hephaestin
