2,3 DPG, how is it produced in RBC and how does it interact with Hb; what is its relevance in altitude exposure, anemia and stored blood
what is the interactino of 2,3 DPG with Hb?
1:1 binding of beta subunit of deoxy Hb molecules conformational change in Hb molecule leading to right shift of ODC curve (Bohr effect) this increase off loading at low pO2 shifts p50 to the right reduce affinity of O2
how is 2,3 DPG produced? What does the pathyway called?
2,3 DPG produced in RBC as side chain of glycolysis by Embden-Meyerhof pathyway ( RBC has a mayer, called Emden mayer off) Found in cell not dependent on aerobic metabolism
what is 2,3 DPG
2,3 diphosphoglycerol
what is Bohr effect ?
Physiological phenomenon first described in 1904 by the Danish physiologist Christian Bohr, stating that hemoglobin's oxygen binding affinity is inversely related both to acidity and to the concentration of carbon dioxide
why in fetal OHDC is not affected by the production of 2,3 DPG
because fetal Hb is 2alpha 2 gamma; 2,3 DPG only binds to beta subunit of Hb
Production of 2,3 DPG is increased by what?
increase in temp, pH of plasma reduce in pO2, as in COPD, altitude and anemia
Anemia effect on 2,3 DPG
it's relative hypoxia, increase 2,3 DPG right shift of ODC, reduce O2 affinity, enhance unloading, p50 is 4 mmHg higher than normal
altitude effect on 2,3 DPG
reduce PaO2, increase RR, MV, increase pH (increase 2,3 DPG ) causing right shift of ODC, p50 increase, enhance unloading of oxygen increase oxygen carrying capacity to peripheries in light of low pO2 at the expense of reduce loading of O2 pulmonary capillary
stored blood effect on 2,3 DPG
stored blood, temperature reduced reduce glycolysis in RBC, reduce 2,3 DPG Left shift of ODC the production restored in 24 hrs of transfusion
