RBCenergy

Question 1

what does a G6PD glucose 6 phaspate dehydrogenase defeiceincy lead to

Answer 1

a hemolytic high bilirubin count

Question 2

what is extravascular hemolysis

Answer 2

No RBC lysis in vascular when they are old and inelastic the RBC are trapped in the spleen and phagocytosed by macrophages.

Question 3

what is hereditary spherocytosis

Answer 3

spectrin mutation leads to rounded short lived cells most common in the plasma membrane defect of the cytoskeleton.

Question 4

what is intravascular hemolysis

Answer 4

when the mechanical stress leads to cells breaking playing the bongos for too long. Release of Hemoglobin from RBC and leads to a Hemoglobinuria

Question 5

what is extravascular hemolysis

Answer 5

removal of old RBC by spleen releasese bilirubin and can cause jaundice.

Question 6

what are the four purposes of RBC metabolism

Answer 6

keeping iron in the Fe2+ state for NADH, maintaining K+/Ca2+ gradients for ATP, keeping the protein SH groups reduced NADPH, and maintaining cell shape ATP.

Question 7

what happens if RBC metabolism fails

Answer 7

cells fill will Ca2+ cells release K+ and they lose the biconcave shape.

Question 8

what are the two ways that RBC deal with glucose and fatty acids

Answer 8

they use glycoloysis and the PPP pathway and they do not use fatty acids only glucose.

Question 9

what does the PPP make

Answer 9

NADPH to keep the SH groups oxidized

Question 10

how is glycoslysis different in the RBC

Answer 10

it does not need insulin to uptake the glucose and doesn’t respond to glucagon as well.

Question 11

what happends with the extra NADH that is made in glycoslysis in an RBC

Answer 11

makes pyruvate into lactate

Question 12

what are the regulatory steps in the glycolysis in RBC

Answer 12

hexokinase and phosphofructokinase 1 not responseive to insulin and is responsive to PH

Question 13

what is the energy clutch

Answer 13

through the 2,3 bisphosphoglycerate it can still make the NADH without making the ATP so it can skip the energy production if needed.

Question 14

how does PH effect glycolysis

Answer 14

acidic PH inhibits glycolysis leading to less lactate protection inhibitw PFK 1

Question 15

what happens to 2,3 BPG synthesis at low PH and how does this effect O2 loading and unloading

Answer 15

Reduces 2,3 BPG and this improves oxygen saturation, this will improve the affinity at the lung leading to better O2 loading, but the boar effect will lead to an increase in unloading at the target tissue that is very acidic.

Question 16

what happens with the pentos phosphate during the PPP in a RBC

Answer 16

through a sercies of transaldolase and transketolase reactions they are reintroduced into the glycolysis pathway and then excreted.

Question 17

what is glutathione and what does it do

Answer 17

is an antioxidant protects the RBC from the sulfer groups and detoxes hydrogen peroxide H2O2 after its made from O2- by superoxide dismutase.

Question 18

what does glutathine need to convert h2o2 to 2 h20

Answer 18

NADPH is needed from the PPP

Question 19

what do enzymatic problems cause

Answer 19

nonspherocytic anemia,

Question 20

what does a G6PD deficiency cause

Answer 20

hemolytic anemia for lack of NADPH needed for glutathion

Question 21

what does a pyruvate kinase deficiency cause

Answer 21

hemolytic anemia for lack of NADH and ATP

Question 22

tell me about a g6PD deficiency

Answer 22

x linked prevalent in Africa and Mediterranean, hemolytic crisis triggered by infection h2o2 producing drugs like antimalarial and flava beans causes splenomegaly and jaundice and RBC with a bite out of them by macrophages.

Question 23

tell me about Pyruvate kinase deficiency

Answer 23

hereditary non spherocytic hemolytic anemia, crisis not triggered by ROS leads to splenomegaly and jaundice. Black spots in the RBC

Question 24

what does fluoride/potassium oxalate do to RBC

Answer 24

stops glycolysis with fouride and exalate is an anticoagulatn used to measure glucose or lactate

Question 25

tell me about the metabolism of cancer cells

Answer 25

tumor cells get energy from glycolysis making lots of lactate and do it under hypoxic condition so they express hypoxia inducible factor to support anaerobic metabolism

Question 26

how do you treat someone with RBC cytoskeletal defects

Answer 26

most common is the ankyrin mutation and it can be treated by removal of the spleen.