scholarly journals Evolution of mammalian hemoglobin function

Blood ◽  
1981 ◽  
Vol 58 (2) ◽  
pp. 189-197 ◽  
Author(s):  
HF Bunn
Keyword(s):  
Oxygen Affinity ◽  
Red Cells ◽  
Red Cell ◽  
Low Oxygen ◽  
Wide Range ◽  
Blood Oxygen Affinity ◽  
Low Levels ◽  
Major Factors ◽  
2,3 Dpg ◽  
Low Oxygen Affinity

Abstract Throughout their evolution, mammalian hemoglobins have acquired a broad repertoire of functional properties well suited to the internal milieu of the red cell. Mammals display a wide range in whole blood oxygen affinity dependent on three major factors: the intrinsic oxygen affinity of the hemoglobin, the level of red cell 2,3-DPG, and the response of the hemoglobin to 2,3-DPG. The concentration of 2,3-DPG varies among groups of mammals. Those animals (cats and ruminants) that have very low levels of this intracellular mediator have hemoglobins of intrinsically low oxygen affinity that fail to respond to the addition of 2,3-DPG. Mammals that have adapted to various types of hypoxia tend to have increased oxygen affinity, primarily mediated through reduced levels of red cell 2,3-DPG. In contrast, mammals who are experimentally subjected to low oxygen tensions develop decreased oxygen affinity owing to increased red cell 2,3-DPG. Mammals employ one of three different mechanisms for the maintenance of higher oxygen affinity of fetal red cells, compared to maternal red cells. Many of these phenomena can be satisfactorily explained at the molecular level but their adaptational significance is less clear.

Evolution of mammalian hemoglobin function

Blood ◽  
1981 ◽  
Vol 58 (2) ◽  
pp. 189-197 ◽  
Author(s):  
HF Bunn
Keyword(s):  
Oxygen Affinity ◽  
Red Cells ◽  
Red Cell ◽  
Low Oxygen ◽  
Wide Range ◽  
Blood Oxygen Affinity ◽  
Low Levels ◽  
Major Factors ◽  
2,3 Dpg ◽  
Low Oxygen Affinity

Throughout their evolution, mammalian hemoglobins have acquired a broad repertoire of functional properties well suited to the internal milieu of the red cell. Mammals display a wide range in whole blood oxygen affinity dependent on three major factors: the intrinsic oxygen affinity of the hemoglobin, the level of red cell 2,3-DPG, and the response of the hemoglobin to 2,3-DPG. The concentration of 2,3-DPG varies among groups of mammals. Those animals (cats and ruminants) that have very low levels of this intracellular mediator have hemoglobins of intrinsically low oxygen affinity that fail to respond to the addition of 2,3-DPG. Mammals that have adapted to various types of hypoxia tend to have increased oxygen affinity, primarily mediated through reduced levels of red cell 2,3-DPG. In contrast, mammals who are experimentally subjected to low oxygen tensions develop decreased oxygen affinity owing to increased red cell 2,3-DPG. Mammals employ one of three different mechanisms for the maintenance of higher oxygen affinity of fetal red cells, compared to maternal red cells. Many of these phenomena can be satisfactorily explained at the molecular level but their adaptational significance is less clear.

Regulation of Blood Oxygen Affinity in the Australian Blackfish Gadopsis Marmoratus: I. Correlations between Oxygen-binding Properties, Habitat and Swimming Behaviour

1982 ◽  
Vol 99 (1) ◽  
pp. 223-243
Author(s):  
G. P. DOBSON ◽  
J. BALDWIN
Keyword(s):  
Whole Blood ◽  
Oxygen Affinity ◽  
Swimming Behaviour ◽  
Oxygen Binding ◽  
Blood Oxygen ◽  
Low Oxygen ◽  
Binding Properties ◽  
Molar Ratios ◽  
Blood Oxygen Affinity ◽  
Low Oxygen Affinity

1. The regulation of whole blood oxygen affinity in the freshwater blackfish Gadopsis marmoratus Richardson has been examined, and correlations made between oxygen-binding properties and the habitat and swimming behaviour of the fish. 2. Blackfish whole blood has a low oxygen affinity relative to other fish bloods reported in the literature. This is not due to a low oxygen affinity of the stripped haemoglobins, but arises from interactions between haemoglobin and intraerythrocytic modulators. 3. The presence of high concentrations of ATP, and to a lesser extent GTP, in the erythrocyte, together with the effect of these nucleoside triphosphates on the oxygen affinity of haemoglobin solutions at physiological NTP: Hb4 molar ratios, demonstrates that this class of compounds is a major regulator of oxygen affinity in blackfish blood. 4. The oxygen affinities of whole blood and haemoglobin solutions are sensitive to pH, with haemoglobin solutions displaying a relatively large alkaline Bohr coefficient of - 1.05 over the physiologically relevant pH range of 6.5–7.0. 5. Although increasing Pco2, lowers the oxygen affinity of whole blood, it does so only through the effect on pH, as pH-buffered haemoglobin solutions show no oxygen-linked CO2 binding. This lack of oxygen-linked CO2 binding has not been reported for any other naturally occurring vertebrate haemoglobins. 6. Muscle morphology and biochemistry, and behavioural observations, indicate that the blackfish uses anaerobic energy metabolism during rapid swimming and in recovery. 7. It is concluded that the oxygen-binding properties of blackfish blood reflect adaptations for maintaining adequate tissue oxygenation for animals at rest and during slow sustained swimming in waters of high oxygen tensions.

scholarly journals Hemoglobin Function in the Horse: The Role of 2,3-Diphosphoglycerate in Modifying the Oxygen Affinity of Maternal and Fetal Blood

Blood ◽  
1973 ◽  
Vol 42 (3) ◽  
pp. 471-479 ◽  
Author(s):  
H. Franklin Bunn ◽  
Hyram Kitchen
Keyword(s):  
Oxygen Saturation ◽  
Oxygen Affinity ◽  
Fetal Hemoglobin ◽  
Red Cells ◽  
Red Cell ◽  
Fetal Blood ◽  
Atp Levels ◽  
2,3 Dpg

Abstract The blood of the newborn horse was found to have a higher affinity for oxygen than that of the mother. This difference was due to the fact that the red cells of newborn foals contained 36% lower 2,3-diphosphoglycerate (2,3-DPG) than red cells from their respective mares. The ATP levels of foal and maternal red cells did not differ significantly. Following birth a prompt rise in the foal's red cell 2,3-DPG occurred, approaching normal (maternal) levels within 5 days. Unlike many other species, the hemoglobins of the newborn and adult horse have been shown to be structurally identical. Furthermore, phosphate-free solutions of newborn and maternal hemoglobins had identical oxygen saturation curves in the absence and presence of added 2,3-DPG. This study demonstrates that, in contrast to other species. the increased oxygen affinity of horse fetal red cells is due to a lower level of the cofactor 2,3-DPG rather than to the presence of fetal hemoglobin.

Physiologic effects of normal-or low-oxygen-affinity red cells in hypoxic baboons

1977 ◽  
Vol 232 (1) ◽  
pp. H79-H84 ◽  
Author(s):  
J. I. Spector ◽  
C. G. Zaroulis ◽  
L. E. Pivacek ◽  
C. P. Emerson ◽  
C. R. Valeri
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cell Mass ◽  
Oxygen Affinity ◽  
Red Cell ◽  
Low Oxygen ◽  
Systemic Oxygen ◽  
Hypoxic State ◽  
Arterial Po2 ◽  
2,3 Dpg

Baboons were bled one-third their red cell mass and were given homologous transfusions of red blood cells to restore the red cell volume. One group of baboons received red blood cells with a normal 2,3-diphosphoglycerate 2,3-DPG) level and normal affinity for oxygen, and in this group the 2,3-DPG level after transfusion was normal. The other group received red blood cells with a 160% of normal 2,3-DPG level and decreased affinity for oxygen, and in this group the 2,3-DPG level after transfusion was 125% of normal. In both groups of baboons, the inspired oxygen concentration was lowered and arterial PO2 tension was maintained at 55-60 mmHg for 2 h after transfusion. During the hypoxic state, systemic oxygen extraction was similar in the two groups, whereas oxygen saturation was lower in the high 2,3-DPG group than in the control animals. Cardiac output was significantly reduced 30 min after the arterial PO2 was restored to normal. These data indicate that red blood cells with decreased affinity for oxygen maintained satisfactory oxygen delivery to tissue during hypoxia.

scholarly journals Oxygenation in Anemic Newborn Lambs with High or Low Oxygen Affinity Red Cells

1981 ◽  
Vol 15 (12) ◽  
pp. 1500-1503 ◽  
Author(s):  
M R Van Ameringen ◽  
J C Fouron ◽  
H Bard ◽  
J C Le Guennec ◽  
J Prosmanne
Keyword(s):  
Oxygen Affinity ◽  
Red Cells ◽  
Low Oxygen ◽  
Low Oxygen Affinity

scholarly journals Rat embryonic and foetal erythrocytes. High 2,3-bisphosphoglycerate and ATP and low oxygen affinity in vitro for nucleated embryonic cells

1980 ◽  
Vol 192 (1) ◽  
pp. 355-359 ◽  
Author(s):  
J G Gilman
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
Red Cells ◽  
Embryonic Cells ◽  
Low Oxygen ◽  
Foetal Life ◽  
High Oxygen Affinity ◽  
Low Oxygen Affinity

Embryonic nucleated red cells of the rat have high ATP and 2,3-bisphosphoglycerate and relatively low oxygen affinity. During foetal life they are replaced by large non-nucleated red cells with high ATP, low bisphosphoglycerate and high oxygen affinity. After birth, small non-nucleated red cells with high bisphosphoglycerate and low oxygen affinity rapidly predominate.

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