Bohr effect and slope of the oxygen dissociation curve after physical training

1982 ◽  
Vol 52 (6) ◽  
pp. 1524-1529 ◽  
Author(s):  
K. M. Braumann ◽  
D. Boning ◽  
F. Trost
Keyword(s):  
Venous Blood ◽  
Training Period ◽  
Dissociation Curve ◽  
Period Increase ◽  
Oxygen Dissociation ◽  
Small Rise ◽  
Dissociation Curves ◽  
O2 Dissociation

Three O2 dissociation curves from venous blood [taken at rest (A), after in vitro acidification with lactic acid (B), and after exhaustive exercise (C)] were determined in eight athletes twice in a year in detrained and fully trained state. The steepness of the standard O2 dissociation curve becomes greater during the training period (increase in Hill's n from 2.68 +/- 0.10 to 2.96 +/- 0.15). There was a concomitant small rise in the intraerythrocytic organic phosphate concentrations. Bohr coefficients (BC) were calculated for blood O2 saturations ranging from 10 to 80% by comparing the dissociation curves A and B (“in vitro” BC) and curves A and C (“in vivo” BC). In detrained and trained state the in vivo BC show their maximal values at low saturation levels, in contrast the in vitro BC exhibit maximal values at middle saturations. During the training period there was an increase in the in vivo BC as well as in the in vitro BC at low saturations. These alterations may lead to augmented O2 extraction from a given volume of blood by up to 15% during heavy work in trained state. The reason for these observations could be an altered erythrocyte population.

The Lack of Effects of Phototherapy on Neonatal Oxygen Dissociation Curves and Hemoglobin Concentration in Vivo

PEDIATRICS ◽  
1977 ◽  
Vol 59 (6) ◽  
pp. 1027-1031
Author(s):  
Barry D. Chandler ◽  
William J. Cashore ◽  
Pierre J. P. Monin ◽  
William Oh
Keyword(s):  
Serum Bilirubin ◽  
Hemoglobin Concentration ◽  
Control Group ◽  
Dissociation Curve ◽  
Oxygen Dissociation ◽  
The Right ◽  
Dissociation Curves ◽  
2,3 Dpg

Phototherapy has been shown to cause hemolysis of fetal red cells and a shift to the right in the neonatal oxygen dissociation curve (ΔP50) in vitro. To determine if these parameters act similarly in vivo, we have studied 16 icteric infants before and after phototherapy and compared them with eight control infants studied at birth and at 3 days of age, measuring the change in P50, 2,3-diphosphoglycerate (2,3-DPG), serum bilirubin, the percent of bilirubin/albumin saturation, and the hemoglobin concentration in the two groups. Following phototherapy, in the icteric infants there was a shift to the right in the O2 dissociation curve of + 1.7 mm Hg, a rise in 2,3-DPG of 2.26 µmol/gm Hb, a fall in serum bilirubin of 4.3 mg/100 ml, a decrease in percent bilirubin/albumin saturation of 12.4%, and a drop in hemoglobin of 1.1 gm/100 ml. The control group showed a ΔP50 of + 2.0 mm Hg, a rise in 2,3-DPG of 3.67 µmol/gm Hb, an increase in serum bilirubin of 3.2 mg/100 ml, an increase in percent bilirubin/albumin saturation of 9.3%, and a fall in hemoglobin of 0.3 gm/100 ml. Significant differences between the groups were seen only in the changes in bilirubin concentration and percent bilirubin/albunmin saturation. The magnitude of changes in P50, 2,3-DPG, and hemoglobin concentration was similar in the phototherapy and control groups and was related to the expected changes with reference to postnatal age. These results suggest that phototherapy in vivo neither affects fetal erythrocytic affinity for oxygen nor causes hemolysis.

A Mathematical Treatment of the Blood Dissociation Curve for Oxygen

1963 ◽  
Vol 9 (6) ◽  
pp. 745-762 ◽  
Author(s):  
Rodolfo Margaria
Keyword(s):  
Dissociation Constants ◽  
Quantitative Description ◽  
Mathematical Treatment ◽  
Physiological Effects ◽  
Functional Importance ◽  
Acidic Group ◽  
Oxygen Dissociation ◽  
Dissociation Curves

Abstract A quantitative description of Bohr's effect can be made from the oxygen dissociation curves of hemoglobin at different pHs, and the dissociation constants of the 02-linked acidic group of Hb (KR) and Hb02 (Ko) have been calculated as, respectively, 1.29 1O-8 and 3.42 10-7 at37°. On the assumption that the oxygenation of hemoglobin takes place in four successive steps, the constant for each equilibrium can easily be calculated, and the values given. It appears that the oxygenation takes place with the same affinity for the first three steps, while the affinity for the fourth oxygenation is 125 times greater. On the basis of these results a simplification of Adair's formula is given, containing only two constants, one (K) being representative of the affinity of the oxygen for the first three hemes, and the other (in)being the increase of affinity for the fourth oxygenation. This formula seems to fit most data in the literature of hemoglobin solutions and of blood in vivo and in vitro. The physiological effects and the functional importance of the increased affinity for the fourth oxygenation are described, and the possibility that disturbances of the Hb oxygenation process may be due to the lack of this process is considered.

scholarly journals No evidence of hemoglobin damage by SARS-CoV-2 infection

Haematologica ◽  
2020 ◽  
Vol 105 (12) ◽  
pp. 2769-2773 ◽  
Author(s):  
Anthony W. DeMartino ◽  
Jason J. Rose ◽  
Matthew B. Amdahl ◽  
Matthew R. Dent ◽  
Faraaz A. Shah ◽  
...  
Keyword(s):  
Pearson Correlation ◽  
Venous Blood ◽  
Blood Gases ◽  
Medical Community ◽  
Dissociation Curve ◽  
Prosthetic Group ◽  
Oxygen Dissociation ◽  
Heme Prosthetic Group ◽  
Dissociation Curves ◽  
Underlying Pathophysiology

SARS-CoV-2 disease (COVID-19) has affected over 22 million patients worldwide as of August 2020. As the medical community seeks better understanding of the underlying pathophysiology of COVID-19, several theories have been proposed. One widely shared theory suggests that SARS-CoV-2 proteins directly interact with human hemoglobin (Hb) and facilitate removal of iron from the heme prosthetic group, leading to the loss of functional hemoglobin and accumulation of iron. Herein, we refute this theory. We compared clinical data from 21 critically ill COVID-19 patients to 21 non-COVID-19 ARDS patient controls, generating hemoglobin-oxygen dissociation curves from venous blood gases. This curve generated from the COVID-19 cohort matched the idealized oxygen-hemoglobin dissociation curve well (Pearson correlation, R2 = 0.97, P<0.0001; CV(RMSD) = 7.3%). We further analyzed hemoglobin, total bilirubin, lactate dehydrogenase, iron, ferritin, and haptoglobin levels. For all analyzed parameters, patients with COVID-19 had similar levels compared to patients with ARDS without COVID-19. These results indicate that patients with COVID-19 do not exhibit any hemolytic anemia or a shift in the normal hemoglobin-oxygen dissociation curve. We therefore conclude that COVID-19 does not impact oxygen delivery through a mechanism involving red cell hemolysis and subsequent removal of iron from the heme prosthetic group in hemoglobin.

scholarly journals A Study of the Sickling Phenomenon and Oxygen Dissociation Curve in Patients with Hemoglobins SS, SD, SF and SC

Blood ◽  
1969 ◽  
Vol 34 (5) ◽  
pp. 682-690 ◽  
Author(s):  
M. J. CAWEIN ◽  
R. P. O’NEILL ◽  
L. A. DANZER ◽  
E. J. LAPPAT ◽  
THOMAS ROACH
Keyword(s):  
Venous Blood ◽  
Cell Formation ◽  
Oxygen Dissociation Curve ◽  
Normal Curve ◽  
Dissociation Curve ◽  
Sickle Cells ◽  
Oxygen Dissociation ◽  
Effect Of Therapy ◽  
The Right ◽  
Dissociation Curves

Abstract 1. Data on pO2, T50, n values and per cent of sickle cells were obtained in patients with hemoglobins SS, SD, SF (S-thalassemia) and SC. In general the per cent of sickle cells was proportional to the per cent of hemoglobin S. The number of sickle cells was, however, influenced by the other type of hemoglobin present and by the pO2. Values for T50 were greater than normal, and values for n were less than normal. 2. The effect of therapy with O2, CO2, NaHCO3 and MgSO4 on the per cent of sickle cells in arterial and venous blood was determined. Only inhalation of O2 reduced the per cent of sickle cells. 3. The rate of sickle cell formation and its reversal were determined under conditions of deoxygenation and oxygenation. These were found to be a function of the type of hemoglobin combinations present. 4. The oxygen dissociation curves were found to be shifted to the right of the normal curve indicating a decreased affinity for oxygen. In two patients the Bohr effect was determined and found to be normal.

scholarly journals Oxygen dissociation curves of rat blood in vitro and in vivo

2007 ◽  
Vol 21 (5) ◽  
Author(s):  
Timothy B. Bentley ◽  
Bozena Kowalska ◽  
Niluka Wickramaratne
Keyword(s):  
Rat Blood ◽  
Oxygen Dissociation ◽  
Dissociation Curves

Letter to the Editor

PEDIATRICS ◽  
1982 ◽  
Vol 70 (3) ◽  
pp. 501-501
Author(s):  
Michel A. Bureau
Keyword(s):  
Maternal Smoking ◽  
Hemoglobin Concentration ◽  
Dissociation Curve ◽  
Preliminary Results ◽  
Left Shift ◽  
Letter To The Editor ◽  
Oxygen Dissociation ◽  
Dissociation Curves ◽  
O2 Dissociation Curve ◽  
O2 Dissociation

The valuable comments of Christoffel are much appreciated. It is said that newborns do adapt to carboxyhemoglobin poisoning (from smoking) by increasing their hemoglobin concentration in blood. Recently, we have further explored the adaptability of newborns to maternal smoking by a study of oxygen dissociation curves in newborns of smoking mothers. Our preliminary results showed that the newborn adapts to maternal and fetal increases in HbCO by a very small left shift in the Hb-O2 dissociation curve and by an increase in hemoglobin.1

The procoagulant effects of factor V Leiden may be balanced against decreased levels of factor V and do not reflect in vivo thrombin formation in newborns

2006 ◽  
Vol 95 (03) ◽  
pp. 434-440 ◽  
Author(s):  
Satu Hyytiäinen ◽  
Ulla Wartiovaara-Kautto ◽  
Veli-Matti Ulander ◽  
Risto Kaaja ◽  
Markku Heikinheimo ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Platelet Rich Plasma ◽  
Venous Blood ◽  
Factor V Leiden ◽  
Factor V ◽  
Cord Plasma ◽  
Adult Plasma ◽  
Thrombin Formation

SummaryThrombin regulation in newborns remains incompletely understood.We studied tissue factor-initiated thrombin formation in cord plasma in vitro, and the effects of Factor VLeiden (FVL) heterozygosity on thrombin regulation both in vitro and in vivo in newborns. Pregnant women with known thrombophilia (n=27) were enrolled in the study. Cord blood and venous blood at the age of 14 days were collected from 11 FVL heterozygous newborns (FVL-positive) and from 16 FVL-negative newborns. Prothrombin fragment F1+2 and coagulation factors were measured. Tissue factor-initiated thrombin formation was studied in cord platelet-poor plasma (PPP) of FVL-negative and -positive newborns, and in both PPP and platelet-rich plasma (PRP) of healthy controls. The endogenous thrombin potential (ETP) in cord PPP or PRP was ∼60% of that in adult plasma, while thrombin formation started ∼55% and ∼40% earlier in cord PPP and PRP, respectively. Further, in FVL-positive newborns thrombin formation started significantly earlier than in FVL-negative newborns. Exogenous activated protein C (APC) decreased ETP significantly more in cord than in adult PRP. In FVL-negative cord plasma 5nM APC decreased ETP by 17.4±3.5% (mean±SEM) compared with only 3.5±3.8% in FVL-positive cord plasma (p=0.01). FVL-positive newborns showed similar levels of F1+2 but significantly decreased levels of factor V compared with FVL negative newborns both in cord plasma (FV 0.82±0.07 U/ml vs. 0.98±0.05 U/ml, p=0.03) and at the age of two weeks (FV 1.15±0.04 U/ml vs. 1.32±0.05 U/ml, p=0.03). In conclusion, newborn plasma showed more rapid thrombin formation and enhanced sensitivity to APC compared with adult plasma. FVL conveyed APC resistance and a procoagulant effect in newborn plasma. Lack of elevated F1+2 levels in FVL-positive infants, however, suggested the existence of balancing mechanisms; one could be the observed lower level of factor V in FVL heterozygous newborns.

The oxygen dissociation curve of haemoglobin in dilute solution

1936 ◽  
Vol 120 (819) ◽  
pp. 484-495 ◽  
Keyword(s):  
Spectroscopic Method ◽  
Marked Change ◽  
Maternal Blood ◽  
Gas Analysis ◽  
Dilute Solution ◽  
Dissociation Curve ◽  
Foetal Haemoglobin ◽  
Oxygen Dissociation ◽  
Dissociation Curves ◽  
The Relationship

The spectroscopic determination of the oxygen dissociation curves of haemoglobin has an advantage over the tonometer and gas analysis method, in that much smaller quantities of haemoglobin can be made use of. The spectroscopic method was used to determine the relationship between the foetal and maternal haemoglobins in the sheep during a study of foetal respiration made by Barcroft (1935). The conditions for the comparison of the haemoglobins were a dilute solution of the haemoglobin at p H 9·2 (borate buffer) and at 20° C. These conditions were chosen because of the very accurate determinations of the dissociation curves of dilute haemoglobin of the sheep by Forbes and Roughton (1931) and because these authors recommend p H 9·2 at room temperature as most suitable for a study of the oxygen equilibrium of haemoglobin, all the haemoglobin being in the form of the alkali salt. McCarthy (1933) and Hall (1934) had found previously that the haemoglobins of the foetal and maternal goat were different, the foetal haemoglobin (in the blood and as purified haemoglobin) having a higher affinity for oxygen. The same relationship was found to exist in the sheep haemoglobins in dilute solution at 20° C and p H 9·2. When samples of human foetal and maternal blood (sent by Professor Fleming from the Obstetrical Department of the Royal Free Hospital) were compared in dilute solution it was found that the foetal haemoglobin had a lower affinity for oxygen than the maternal. This was also found by Haurowitz (1935) for dilute solutions of the haemoglobins of mother and new born infant. Haurowitz, however, pointed out that in the corpuscles the affinity for oxygen is less in the infant’s haemoglobin than in that of the mother, but the method used by him did not allow of measurements on suspensions of corpuscles. In the present work the dissociation curves of dilute suspensions of corpuscles have been compared with similar solutions of the haemoglobin. It was found that the relationship of the dissociation curves for human foetal and maternal corpuscles is the same as that found by Barcroft in the goat and in the sheep. It has now been found that by a dilution of human adult haemoglobin the dissociation curve is altered by 200% to a position of higher affinity for oxygen, without any marked change in shape. The haemoglobin of the human foetus, on the other hand, is much less affected by dilution, thus explaining the anomaly of the reversed relationship when solutions of the haemoglobins are used instead of suspensions of corpuscles. It was shown by the work of Bock, Field, and Adair (1924), and by Adair (1925), that a solution of haemoglobin free from stromata and of a similar concentration to blood gives a dissociation curve like whole blood. This makes it clear that in the comparison of dilute haemoglobin solutions with suspensions of corpuscles we are concerned, not simply with a change in the haemoglobin due to haemolysis, but a change due to a dilution of the contents of the corpuscle.

scholarly journals Oxygen and Carbon Dioxide Transport Characteristics of the Blood of the Nile Monitor Lizard (Varanus Niloticus)

1987 ◽  
Vol 130 (1) ◽  
pp. 27-38
Author(s):  
JAMES W. HICKS ◽  
ATSUSHI ISHIMATSU ◽  
NORBERT HEISLER
Keyword(s):  
Carbon Dioxide ◽  
Haemoglobin Concentration ◽  
Oxygen Affinity ◽  
Total Blood ◽  
Carbon Dioxide Transport ◽  
Monitor Lizard ◽  
The Right ◽  
Dissociation Curves

Oxygen and carbon dioxide dissociation curves were constructed for the blood of the Nile monitor lizard, Varanus niloticus, acclimated for 12h at 25 and 35°C. The oxygen affinity of Varanus blood was low when Pco2 w a s in the range of in vivo values (25°C: P50 = 34.3 at PCOCO2 = 21 mmHg; 35°C: P50 = 46.2 mmHg at PCOCO2 = 35 mmHg; 1 mmHg = 133.3 Pa), and the oxygen dissociation curves were highly sigmoidal (Hill's n = 2.97 at 25°C and 3.40 at 35°C). The position of the O2 curves was relatively insensitive to temperature change with an apparent enthalpy of oxygenation (ΔH) of −9.2kJ mol−1. The carbon dioxide dissociation curves were shifted to the right with increasing temperature by decreasing total CCOCO2 at fixed PCOCO2, whereas the state of oxygenation had little effect on total blood CO2 content. The in vitro buffer value of true plasma (Δ[HCO3−]pl/-ΔpHpl) rose from 12.0 mequiv pH−1−1 at 25°C to 17.5 mequiv pH−11−1 at 35°C, reflecting a reversible increase of about 30% in haemoglobin concentration and haematocrit levels during resting conditions in vivo.

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