Oxygen transport in blood at high altitude: role of the hemoglobin?oxygen affinity and impact of the phenomena related to hemoglobin allosterism and red cell function

2003 ◽  
Vol 90 (3-4) ◽  
pp. 351-359 ◽  
Author(s):  
Michele Samaja ◽  
Tiziano Crespi ◽  
Marco Guazzi ◽  
Kim D. Vandegriff
Keyword(s):  
High Altitude ◽  
Oxygen Transport ◽  
Cell Function ◽  
Oxygen Affinity ◽  
Red Cell ◽  
Hemoglobin Oxygen Affinity

scholarly journals High altitude genetic adaptation in Tibetans: No role of increased hemoglobin–oxygen affinity

2014 ◽  
Vol 53 (1-2) ◽  
pp. 27-29 ◽  
Author(s):  
Tsewang Tashi ◽  
Tang Feng ◽  
Parvaiz Koul ◽  
Ricardo Amaru ◽  
Dottie Hussey ◽  
...  
Keyword(s):  
High Altitude ◽  
Oxygen Affinity ◽  
Genetic Adaptation ◽  
Hemoglobin Oxygen Affinity

Red cell oxygen affinity in fetal sheep: role of 2,3-DPG and adult hemoglobin

1978 ◽  
Vol 45 (1) ◽  
pp. 7-10 ◽  
Author(s):  
H. Bard ◽  
J. C. Fouron ◽  
J. E. Robillard ◽  
A. Cornet ◽  
M. A. Soukini
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Oxygen Affinity ◽  
Fetal Life ◽  
Red Cell ◽  
Adult Type ◽  
Fetal Sheep ◽  
Adult Hemoglobin ◽  
Relationship Of

Studies were carried out during fetal life in sheep to determine the relationship of 2,3-diphosphoglycerate (DPG), the intracellular red cell and extracellular pH, and the switchover to adult hemoglobin synthesis in regulating the position of the fetal red cell oxygen-affinity curve in utero. Adult hemoglobin first appeared near 120 days of gestation. The mean oxygen tension at which hemoglobin is half saturated (P50) prior to 120 days of gestation remained constant at 13.9 +/- 0.3 (SD) Torr and then increased gradually as gestation continued, reaching 19 Torr at term. During the interval of fetal life studied, the level of DPG was 4.43 +/- 1.63 (SD) micromol/g Hb and the deltapH between plasma and red blood cells was 0.227 +/- 0.038 (SD); neither was affected by gestational age. The decrease in the red cell oxygen affinity after 120 days of gestation ocrrelated with the amount of adult hemoglobin present in the fetus (r = 0.78; P less than 0.001). This decrease can be attributed only to the amount of the adult-type hemoglobin present, and not to DPG, or to changes in the deltapH between plasma and red blood cells, because both remained stable during the last trimester.

NTP pattern of avian embryonic red cells: role of RNA degradation and AMP deaminase/5′-nucleotidase activity

2003 ◽  
Vol 284 (3) ◽  
pp. R771-R779 ◽  
Author(s):  
Rosemarie Baumann ◽  
Robert Götz ◽  
Stefanie Dragon
Keyword(s):  
Hormonal Regulation ◽  
Oxygen Affinity ◽  
Erythroid Differentiation ◽  
Rna Degradation ◽  
Amp Deaminase ◽  
Key Enzymes ◽  
Allosteric Effectors ◽  
Hemoglobin Oxygen Affinity ◽  
Adult Hemoglobin

During terminal erythroid differentiation, degradation of RNA is a potential source for nucleotide triphosphates (NTPs) that act as allosteric effectors of hemoglobin. In this investigation, we assessed the developmental profile of RNA and purine/pyrimidine trinucleotides in circulating embryonic chick red blood cells (RBC). Extensive changes of the NTP pattern are observed which differ significantly from what is observed for adult RBC. The biochemical mechanisms have not been identified yet. Therefore, we studied the role of AMP deaminase and IMP/GMP 5′-nucleotidase, which are key enzymes for the regulation of the purine nucleotide pool. Finally, we tested the effect of major NTPs on the oxygen affinity of embryonic/adult hemoglobin. The results are as follows. 1) Together with ATP, UTP and CTP serve as allosteric effectors of hemoglobin. 2) Degradation of erythroid RNA is apparently a major source for NTPs. 3) Developmental changes of nucleotide content depend on the activities of key enzymes (AMP deaminase, IMP/GMP 5′-nucleotidase, and pyrimidine 5′-nucleotidase). 4) Oxygen-dependent hormonal regulation of AMP deaminase adjusts the red cell ATP concentration and therefore the hemoglobin oxygen affinity.

scholarly journals Mechanism of red cell 2,3-diphosphoglycerate increase in neonatal lambs

Blood ◽  
1983 ◽  
Vol 61 (5) ◽  
pp. 920-924 ◽  
Author(s):  
NA Noble ◽  
CA Jansen ◽  
PW Nathanielsz ◽  
KR Tanaka
Keyword(s):  
Oxygen Affinity ◽  
Glucose Consumption ◽  
Red Cell ◽  
Sequential Effects ◽  
Blood Ph ◽  
Tenfold Increase ◽  
Hemoglobin Oxygen Affinity ◽  
Ph Increase ◽  
Neonatal Lambs

Abstract The tenfold increase in red cell 2,3-diphosphoglycerate (DPG) concentration that occurs during the first 5 days of life in lambs is an important adaptation to extrauterine life. In lambs, DPG reduces hemoglobin oxygen affinity by the Bohr effect. Our data on 10 neonatal lambs suggest that the biochemical mechanism underlying this DPG increase involves the following: (1) a rise in plasma glucose from 40 to 100 mg/dl in the first 48 hr of life, which allows for increased glucose consumption in the highly glucose-permeable neonatal RBC; (2) a transitory rise in blood pH begins at birth, peaks at about 20 hr, and falls slightly; (3) the pH increase coincides with a threefold increase in RBC fructose-1,6-diphosphate (FDP) concentration due, we believe, to pH activation of phosphofructokinase; (4) glycolytic intermediates after the glyceraldehyde-3-phosphate dehydrogenase (GAPD) step do not rise in the first 24 hr of life, possibly due to insufficient inorganic phosphate (Pi), a substrate of GAPD; (5) plasma Pi increases from about 7 mg/dl at birth to 11 mg/dl at 72 hr, activates the GAPD, and FDP levels decline; and (6) the in vitro activity of the DPG synthetic enzyme, DPG mutase, is increased 12-fold in neonatal compared to adult RBC. We conclude that the postnatal rise in DPG is explained at least in part by the sequential effects of these metabolic changes.

What is the Clinical Importance of Alterations of the Hemoglobin Oxygen Affinity in Preserved Blood - Especially as Produced by Variations of Red Cell 2,3 DPG Content?

Vox Sanguinis ◽  
1978 ◽  
Vol 34 (2) ◽  
pp. 111-127 ◽  
Author(s):  
J.C. Bakker ◽  
Ernest Beutler ◽  
John A. Collins ◽  
R. Ben Dawson ◽  
Lars Garby ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
Clinical Importance ◽  
Red Cell ◽  
Hemoglobin Oxygen Affinity ◽  
2,3 Dpg

scholarly journals Living the high life

2016 ◽  
Vol 38 (5) ◽  
pp. 30-33
Keyword(s):  
High Altitude ◽  
Oxygen Transport ◽  
Evolutionary Adaptation

Helen Albert speaks to biological anthropologist Professor Cynthia Beall about her research into human evolutionary adaptation to high altitude and the important role of oxygen transport genes in Tibetan highlanders.

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