scholarly journals Antarctic Fish Blood: Respiratory Properties and the Effects Of Thermal Acclimation

1984 ◽  
Vol 109 (1) ◽  
pp. 265-279
Author(s):  
VILHELM TETENS ◽  
RUFUS M. G. WELLS ◽  
ARTHUR L. DEVRIES
Keyword(s):  
Oxygen Affinity ◽  
Antarctic Fish ◽  
Thermal Acclimation ◽  
Temperate Species ◽  
Molar Ratio ◽  
Oxygen Binding ◽  
Blood Oxygen ◽  
Low Oxygen ◽  
Blood Oxygen Affinity

1. The effects of thermal acclimation on whole blood oxygen affinity were examined in the antarctic fish Pagothenia borchgrevinki. 2. 4.5°C-acclimated fish had a P50 value of 26.7 mmHg at pH 8.1, compared to 20.7 mmHg for −1.5°C-acclimated fish. The apparent heat of oxygenation, ΔH = −26.7 kJ mol−1, is comparable to values for temperate species. 3. Warm-acclimation was followed by an increased ATP: Hb4 molar ratio, resulting in an augmentation of the thermal effect on oxy-haemoglobin affinity. This may be considered adaptive in a constantly well oxygenated environment, where oxygen loading at the gills is secured. Unloading to the tissues is thereby enhanced, supporting an elevated rate of aerobic metabolism at higher temperatures. 4. In vivo blood pH was high, between 8.10 and 8.25 at −1.5°C. Astrup titration revealed arterial CO2 tensions of less than 0.8 mmHg, indicating relative hyperventilation and low oxygen extraction efficiency in antarctic fish. 5. Blood oxygen affinities of four antarctic nototheniid species were low (P50 between 11.9 and 20.7 mmHg at pH 8.1 and --1.5°C) in comparison with the temperate species Notothenia angustata (P50 = 10.8 mmHg). The zoarcid Rhigophila dearborni had a high blood oxygen affinity (P50 = 4.3 mmHg). Blood oxygen-binding properties are discussed in relation to the polar environment, mode of life, and the concept of cold adaptation.

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.

Postnatal regulation of canine oxygen delivery: erythrocyte components affecting Hb function

1980 ◽  
Vol 238 (1) ◽  
pp. H73-H79 ◽  
Author(s):  
P. A. Mueggler ◽  
G. Jones ◽  
J. S. Peterson ◽  
J. M. Bissonnette ◽  
R. D. Koler ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
Fetal Hemoglobin ◽  
Blood Oxygen ◽  
Oxygen Dissociation ◽  
Affinity Change ◽  
Blood Oxygen Affinity ◽  
Postnatal Change ◽  
2,3 Dpg

A rightward shift in the blood oxygen dissociation curve occurs during the 1st mo of canine life. A detailed peptide analysis indicated that dogs do not have a separate fetal hemoglobin. Other erythrocyte components such as ATP, K+, Na+, and H+ were excluded as significant mediators of the postnatal oxygen affinity change. Erythrocyte 2,3-DPG levels essentially zero in fetal dogs, increased rapidly during the 1st mo of canine life. There was a significant correlation between this postnatal 2,3-DPG increase and the postnatal decrease in blood oxygen affinity. Dialyzed hemolysates of fetal or adult canine blood have the same intrinsic oxygen affinity and the same response to normal adult levels of 2,3-DPG. Furthermore, the magnitude and direction of this 2,3-DPG-induced decrease in oxygen affinity in vitro are comparable to the in vivo postnatal change in oxygen affinity.

scholarly journals Oxygen Affinity in Hemoglobin Köln Disease

Blood ◽  
1972 ◽  
Vol 39 (3) ◽  
pp. 398-406 ◽  
Author(s):  
Frank G. de Furia ◽  
Denis R. Miller
Keyword(s):  
Whole Blood ◽  
Normal Values ◽  
Cell Mass ◽  
Oxygen Affinity ◽  
Red Cell ◽  
Blood Oxygen ◽  
Red Cell Mass ◽  
High Oxygen Affinity ◽  
Blood Oxygen Affinity

Abstract Oxygen affinity studies in a splenectomized patient with sporadically occurring Hb Köln disease revealed high whole blood oxygen affinity (P50 O2 17.6 mm Hg) with increased 2, 3-diphosphoglycerate (DPG), low ATP, and normal RBC ΔpH. Isolated electrophoretically slow migrating Hb Köln had a high oxygen affinity, decreased Hill’s number, and normal DPG reactivity. Functional evidence for hybrid tetramers with normal mobility is presented. Partial deoxygenation may play a role in the denaturation of the Hb Köln molecule and thus account for a higher oxygen affinity (low P50 O2), measured by the mixing technique, than the actual values for P50 that exist in vivo. Increased oxygen affinity and decreased P50 O2 would result in increased erythropoiesis and account for a well-compensated hemolytic process in this patient with a normal red cell mass and normal values of hemoglobin.

scholarly journals ALLOSTERIC CONTROL OF OXYGEN BINDING BY HAEMOGLOBIN DURING EMBRYONIC DEVELOPMENT IN THE CROCODILE CROCODYLUS POROSUS: THE ROLE OF RED CELL ORGANIC PHOSPHATES AND CARBON DIOXIDE

1993 ◽  
Vol 175 (1) ◽  
pp. 15-32 ◽  
Author(s):  
G. C. Grigg ◽  
R. M. G. Wells ◽  
L. A. Beard
Keyword(s):  
Embryonic Development ◽  
Whole Blood ◽  
Marked Effect ◽  
Oxygen Affinity ◽  
Oxygen Binding ◽  
Blood Oxygen ◽  
Embryonic Life ◽  
Crocodylus Porosus ◽  
Blood Oxygen Affinity ◽  
2,3 Dpg

The P50 of whole blood [30°C, PCO2=2.08 kPa (15.6 mmHg)] decreases during embryonic development from approximately 6.7 kPa (50 mmHg) at 15 days to about half this value at hatching (86 days), paralleling a decrease in ATP from 100 to 5–10 micromole g-1 Hb. There is also a progressive changeover from embryonic to adult haemoglobin (HbA). A pulse of 2,3- diphosphoglycerate (2,3-DPG) (18 micromole g-1 Hb) occurs late in embryonic life. It has no effect on whole-blood oxygen-affinity and falls rapidly at hatching to values typical of post-hatchling crocodilians in general (<1.0 micromole g-1 Hb). ATP has a marked effect on the oxygen affinity of embryonic haemoglobin (HbE) but not on HbA. 2,3-DPG has only very small effects on the oxygen affinities of HbE and HbA. CO2 has a small effect on the oxygen affinity of HbE but a marked effect on that of HbA. Values of PO2 measured in the chorio-allantoic artery [2.9 kPa (22 mmHg)] and vein [5.9 kPa (52 mmHg)] imply an increase in saturation from approximately 30 % to more than 80 %. Neither whole-blood oxygen-affinity nor ATP level was altered in response to an experimental 7-day exposure to low ambient oxygen levels [10.7 kPa (80 mmHg)]. The results do not lend themselves easily to the pan-selectionist paradigm in which all physiological traits are viewed as being adaptive.

scholarly journals Hypoxic Responses in a Fish From a Stable Environment: Blood Oxygen Transport in the Antarctic Fish Pagothenia Borchgrevinki

1989 ◽  
Vol 141 (1) ◽  
pp. 97-111 ◽  
Author(s):  
R. M.G. WELLS ◽  
G. C. GRIGG ◽  
L. A. BEARD ◽  
G. SUMMERS
Keyword(s):  
Haemoglobin Concentration ◽  
Oxygen Affinity ◽  
Antarctic Fish ◽  
Hypoxic Exposure ◽  
Blood Oxygen ◽  
Low Oxygen ◽  
Pagothenia Borchgrevinki ◽  
Oxygen Carrying Capacity ◽  
O2 Delivery ◽  
The Antarctic

The effects of hypoxic exposure on whole-blood oxygen-affinity were examined in the antarctic fish Pagothenia borchgrevinki. Fish exposed to POO2 = 60 mmHg for 11–14 days at −1.5°C had a P50 value of 20.6±4.8mmHg (S.D., N=13) at pH8.16, compared with 31.1 ±4.3mmHg (N=10) at pH8.00 for normoxic fish. Exposure to low oxygen levels resulted in a significant (66 %) rise in haemoglobin concentration, and erythrocyte [ATP] decreased by approximately 27%. There was no evidence for erythrocyte swelling. An aberrant gill morphology was observed in six fish and these showed unexpectedly high erythrocyte ATP levels. Oxygen-carrying capacity increased by approximately 40% in hypoxic fish and was correlated with a 34 % decrease in spleen mass. Despite the fact that antarctic fish have exceptionally low demands for oxygen and are unlikely ever to encounterenvironmental hypoxia, this antarctic fish has the necessary machinery to respondto hypoxia in a way that is typical of teleosts that naturally inhabit oxylabile environments. The ability to make short-term adaptive changes in the O2 delivery system in response to hypoxic exposure may be typical for vertebrates in general, rather than a feature seen only in those organisms which encounter environmental hypoxia on a regular basis.

Role of erythrocyte organic phosphates in blood oxygen transport in anemic quail

1991 ◽  
Vol 260 (4) ◽  
pp. R798-R803
Author(s):  
M. Riera ◽  
J. F. Fuster ◽  
L. Palacios
Keyword(s):  
Blood Level ◽  
Oxygen Transport ◽  
Oxygen Affinity ◽  
Molar Ratio ◽  
Blood Oxygen ◽  
Compensatory Response ◽  
Organic Phosphates ◽  
Blood Oxygen Affinity ◽  
Additional Influence

The effects of two different degrees of experimentally induced anemia and the consequent high percentage of circulating immature erythrocytes on oxygen affinity (pH 7.5 and 41 degrees C), erythrocyte organic phosphates, and Hb fractions have been studied in quail. Blood reticulocytes reached percentages of 24 and 69-87% in the first and second experiments, respectively. Variations in the phosphate levels found during the anemic process were related to the amount of circulating reticulocytes. The erythrocyte [ATP] (brackets indicate concentration) and [ATP]/[Hb] molar ratio increased with the release of reticulocytes and returned to control levels as they matured. The erythrocyte [inositol pentakisphosphate (InsP5)] decreased significantly when circulating reticulocytes showed their highest values, whereas there was hardly any effect on the [InsP5]/[Hb] molar ratio, which changed only slightly. Hb-O2 affinity also exhibited no statistical changes associated with acute anemia. These latter findings indicate that InsP5, at physiological concentrations, is the primary modulator of quail Hb function; the observed rise in [ATP] has no additional influence on Hb-O2 affinity. It is suggested that InsP5 tends to maintain the blood oxygen affinity in both mature erythrocytes and reticulocytes. The main compensatory response at blood level is a rapid bulk reticulocyte release from medulla.

Respiratory properties of the blood of Amazon fishes

1978 ◽  
Vol 56 (4) ◽  
pp. 898-906 ◽  
Author(s):  
K. Johansen ◽  
C. P. Mangum ◽  
G. Lykkeboe
Keyword(s):  
Carrying Capacity ◽  
Oxygen Affinity ◽  
Oxygen Binding ◽  
Blood Oxygen ◽  
Physiological Variables ◽  
Blood Ph ◽  
Lower Blood ◽  
Blood Oxygen Affinity ◽  
Oxygen Carrying Capacity ◽  
Exchange Medium

Among 17 species of Amazon fishes, the respiratory properties of the blood are clearly correlated with the gas exchange medium. A comparison between species shows that bimodal and obligatory air breathers have, in general, a higher blood oxygen carrying capacity, higher levels of intracellular modulators of oxygen binding, lower blood oxygen affinity, and a larger Bohr shift than water breathers. Within a facultative air-breathing species (Synbranchus marmoratus) removal from water and acute exposure to air (13–44 h) resulted in similar changes in blood respiratory properties. The significance of the respiratory adaptations of the blood, however, is clear only when physiological variables such as blood pH and [Formula: see text] are considered.

scholarly journals Regulation of Blood Oxygen Affinity in the Australian Blackfish Gadopsis Marmoratus: II. Thermal Acclimation

1982 ◽  
Vol 99 (1) ◽  
pp. 245-254
Author(s):  
G. P. DOBSON ◽  
J. BALDWIN
Keyword(s):  
Whole Blood ◽  
Haemoglobin Concentration ◽  
Oxygen Affinity ◽  
Thermal Acclimation ◽  
Acclimation Temperature ◽  
Blood Oxygen ◽  
Molar Ratios ◽  
Oxygen Equilibrium ◽  
Nucleoside Triphosphates ◽  
Blood Oxygen Affinity

1. The effects of thermal acclimation on whole blood oxygen affinity were examined in the freshwater blackfish Gadopsis marmoratus. 2. Oxygen equilibrium curves for 20°C-acclimated fish were shifted to the right of curves obtained for 10°C-acclimated fish when determined at both 20°C and 10°C. Oxygen equilibrium curves obtained for solutions of stripped haemoglobin prepared from blood of 20°C- and 10°C-acclimated fish did not show the differences observed for whole blood. 3. Thermal acclimation did not alter the number, migration rates, or relative amounts of the five electrophoretic forms of haemoglobin present in blackfish blood. 4. The intraerythrocytic concentration of nucleoside triphosphates was higher in the 20°C-acclimated fish than in 10°C-acclimated fish, while the whole blood haemoglobin concentration was lower in the 20 °C-acclimated fish. These differences gave NTP: Hb4 molar ratios of 1.68 for the 20°C-acclimated fish and 1.32 for 10°C-acclimated fish. The effects of nucleoside triphosphates on oxygen affinity were similar for stripped haemoglobins of both acclimation groups. 5. The change in NTP:Hb4 molar ratios with acclimation temperature acts to enhance oxygen unloading to the tissues rather than oxygen uptake at the gills at the higher acclimation temperature. As the waters inhabited by the blackfish retain high oxygen tensions at 20°C, these changes in blood oxygen affinity could be considered adaptive if they were associated with elevated rates of oxygen-dependent metabolism at the higher temperatures.

Increased blood oxygen affinity during digestion in the snakePython molurus

2002 ◽  
Vol 205 (21) ◽  
pp. 3327-3334 ◽  
Author(s):  
Johannes Overgaard ◽  
Tobias Wang
Keyword(s):  
Partial Pressure ◽  
Oxygen Transport ◽  
Oxygen Affinity ◽  
Arterial Oxygen ◽  
Blood Oxygen ◽  
Arterial Blood ◽  
Oxygen Dissociation ◽  
Blood Oxygen Affinity ◽  
Dissociation Curves

SUMMARYMany snakes exhibit large increases in metabolic rate during digestion that place extensive demands on efficient oxygen transport. In the present study,we describe blood oxygen affinity following three weeks of fasting and 48 h after feeding in the Burmese python (Python molurus). We also report simultaneous measurements of arterial blood gases and haematological parameters. Arterial blood was obtained from chronically implanted catheters,and blood oxygen-dissociation curves were constructed from oxygencontent measurements at known oxygen partial pressure(PO2) values at 2% and 5% CO2. Arterial pH remained constant at approximately 7.6 after feeding, but digestion was associated with an approximately 6 mmol l-1 increase in [HCO3-], while CO2 partial pressure(PCO2) increased from 2.21±0.13 kPa in fasted animals to 2.89±0.17 kPa at 48 h after feeding. Blood oxygen affinity in vivo was predicted on the basis of pH in vivoand the blood oxygen-dissociation curves obtained in vitro. The blood oxygen affinity in vivo increased during digestion, with P50 values decreasing from 4.58±0.11 kPa to 3.53±0.24 kPa. This increase was associated with a significant decrease in the red blood cell [NTP]/[Hb4] ratio (relationship between the concentrations of organic phosphates and total haemoglobin) and a significant decrease in mean cellular haemoglobin content, which is indicative of swelling of the red blood cells. Our data for blood oxygen affinity and arterial oxygen levels, together with previously published values of oxygen uptake and blood flows, allow for a quantitative evaluation of oxygen transport during digestion. This analysis shows that a large part of the increased metabolism during digestion is supported by an increased venous extraction, while arterial PO2(PaO2) and haemoglobin saturation do not vary with digestive status. Thus, we predict that venous PO2 (PvO2) is reduced from a fasting value of 5.2 kPa to 1.6 kPa during digestion.

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