Carbon dioxide transport in alligator blood and its erythrocyte permeability to anions and water

1998 ◽  
Vol 274 (3) ◽  
pp. R661-R671 ◽  
Author(s):  
Frank B. Jensen ◽  
Tobias Wang ◽  
David R. Jones ◽  
Jesper Brahm
Keyword(s):  
Carbon Dioxide ◽  
Blood Cells ◽  
Blood Circulation ◽  
Carbon Dioxide Transport ◽  
Blood Flows ◽  
Pulmonary Capillaries ◽  
Effect Binding ◽  
Net Fluxes ◽  
Fixed Acid ◽  
Haldane Effect

Deoxygenation of alligator red blood cells (RBCs) caused binding of two [Formula: see text] equivalents per hemoglobin (Hb) tetramer at physiological pH. At lowered pH, some[Formula: see text] binding also occurred to oxygenated Hb. The erythrocytic total CO2 content was large, and Hb-bound [Formula: see text], free[Formula: see text], and carbamate contributed about equally in deoxygenated cells. The nonbicarbonate buffer values of RBCs and Hb were high, and the Hb showed a significant fixed acid Haldane effect. Binding of [Formula: see text] on deoxygenation occurred without a change in RBC intracellular pH, revealing equivalence between oxylabile[Formula: see text] and H+ binding. Erythrocyte volume, plasma pH, and plasma [Formula: see text]concentration also varied little with the degree of oxygenation. Diffusional water permeability was higher in oxygenated than deoxygenated RBCs. The RBCs have rapid band 3-mediated Cl− and[Formula: see text] transport, which was not affected by degree of oxygenation, but net fluxes of Cl− and[Formula: see text] via the anion exchanger are small during blood circulation at rest. Most of the CO2 taken up into the blood as it flows through tissue capillaries is carried within the erythrocytes as Hb-bound [Formula: see text] until CO2 is excreted when blood flows through pulmonary capillaries.

scholarly journals IN VITRO INTERACTIONS BETWEEN OXYGEN AND CARBON DIOXIDE TRANSPORT IN THE BLOOD OF THE SEA LAMPREY (PETROMYZON MARINUS)

1992 ◽  
Vol 173 (1) ◽  
pp. 25-41 ◽  
Author(s):  
R. A. Ferguson ◽  
N. Sehdev ◽  
B. Bagatto ◽  
B. L. Tufts
Keyword(s):  
Carbon Dioxide ◽  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Whole Blood ◽  
Blood Cells ◽  
Sea Lamprey ◽  
Carbon Dioxide Transport ◽  
Dissociation Curves

In vitro experiments were carried out to examine the interactions between oxygen and carbon dioxide transport in the blood of the sea lamprey. Oxygen dissociation curves for whole blood obtained from quiescent lampreys had Hill numbers (nH) ranging from 1.52 to 1.89. The Bohr coefficient for whole blood was -0.17 when extracellular pH (pHe) was considered, but was much greater (-0.63) when red blood cell pH (pHi) was considered. The pHi was largely dependent on haemoglobin oxygen- saturation (SO2) and the pH gradient across the red blood cell membrane was often reversed when PCO2 was increased and/or SO2 was lowered. The magnitude of the increase in pHi associated with the Haldane effect ranged from 0.169 pH units at 2.9 kPa PCO2 to 0.453 pH units at a PCO2 of 0.2 kPa. Deoxygenated red blood cells had a much greater total CO2 concentration (CCO2) than oxygenated red blood cells, but the nonbicarbonate buffer value for the red blood cells was unaffected by oxygenation. Plasma CCO2 was not significantly different under oxygenated or deoxygenated conditions. Partitioning of CO2 carriage in oxygenated and deoxygenated blood supports recent in vivo observations that red blood cell CO2 carriage can account for much of the CCO2 difference between arterial and venous blood. Together, the results also suggest that oxygen and carbon dioxide transport may not be tightly coupled in the blood of these primitive vertebrates. Finally, red cell sodium concentrations were dependent on oxygen and carbon dioxide tensions in the blood, suggesting that sodium-dependent ion transport processes may contribute to the unique strategy for gas transport in sea lamprey blood.

scholarly journals Oxygen and carbon dioxide transport in vertebrate erythrocytes: an evolutionary change in the role of membrane transport.

1997 ◽  
Vol 200 (2) ◽  
pp. 369-380 ◽  
Author(s):  
M Nikinmaa
Keyword(s):  
Carbon Dioxide ◽  
Teleost Fish ◽  
Oxygen Affinity ◽  
Carbon Dioxide Tension ◽  
Buffering Capacity ◽  
Proton Efflux ◽  
Carbon Dioxide Transport ◽  
Elasmobranch Fish ◽  
Haldane Effect

Two major strategies are apparent for the regulation of gas transport by vertebrate blood except in the myxinoids, which seem to have little scope for such regulation. In lampreys and teleost fish, haemoglobins have low buffering capacities and large Bohr/Haldane effects. Na+/H+ exchange plays an important role in the control of haemoglobin oxygen-affinity in these vertebrate groups. The large Bohr/Haldane effect also facilitates carbon dioxide transport: the blood (or erythrocyte) pH increases upon deoxygenation, thus increasing the concentration of bicarbonate formed at a given carbon dioxide tension. In lampreys, the bicarbonate permeability of the erythrocyte membrane is low. As a consequence, extracellular acid loads cannot be buffered by haemoglobin. In contrast, teleost erythrocytes possess a functional anion exchange, allowing extracellular proton loads to be buffered by haemoglobin. However, because the buffering capacity of teleost haemoglobins is low, buffering of extracellular acid loads is less effective in teleost fish than in elasmobranch fish and in air-breathing vertebrates whose haemoglobins have a high buffering capacity. However, the high buffering capacity of the haemoglobins diminishes the possibility of regulating haemoglobin oxygen-affinity via secondarily active Na+/H+ exchange, because intracellular pH changes, caused by proton efflux, remain small.

Respiratory pigments: interactions between oxygen and carbon dioxide transport

1989 ◽  
Vol 67 (12) ◽  
pp. 2971-2985 ◽  
Author(s):  
C. R. Bridges ◽  
S. Morris
Keyword(s):  
Experimental Data ◽  
Carbon Dioxide ◽  
Venous Blood ◽  
Oxygen Affinity ◽  
Specific Effect ◽  
Carbon Dioxide Transport ◽  
Wide Range ◽  
Lower Vertebrates ◽  
Haldane Effect

Oxygen and carbon dioxide are transported in vertebrates and invertebrates by a wide range of respiratory pigments. These respiratory gases are not transported independently of one another, and this review considers the influence of carbon dioxide on oxygen transport and vice versa. A specific effect of carbon dioxide or bicarbonate, decreasing oxygen affinity, is found in many haemoglobins, but the effect is often reduced in the presence of organic phosphates. Clear experimental data are available for mammalian haemoglobins but in birds and lower vertebrates more data are required to verify the presence and magnitude of the CO2 effect. In erythrocruorins and haemocyanins CO2 increases O2 affinity, whereas in haemerythrins, as in haemoglobin, CO2 again decreases oxygen affinity. Much of our knowledge of invertebrate respiratory pigments is based, however, on data from one or two species. A specific effect of CO2 on O2 affinity has also often been found only at high CO2 partial pressures, which may be outside the physiological range for these species. More in vivo experimental data on CO2 values are required for these species, and further studies on other species may help to explain this discrepancy. The interaction of O2 and CO2 transport is mainly through the Haldane effect, i.e., deoxygenated blood having a greater capacity for CO2 than oxygenated blood. This is due directly to the formation of carbamino groups (carbamate) and also to the fact that deoxygenated blood binds relatively more protons than oxygenated blood. This forms the basis for the linkage between the Bohr and Haldane effects. In some species in which the Bohr coefficient is below −1.0, an akalosis in the tissues may be induced. Large Haldane effects may be particularly effective in promoting CO2 unloading when the partial pressure difference of CO2 between arterial and venous blood is small. Carbamate formation may account for 10–20% of the CO2 transported in mammals, but its role in lower vertebrates and invertebrates has only recently been considered. Carbon dioxide transport is modulated by those factors that influence O2 affinity as these in turn influence the Haldane effect.

Transport: blood and circulation

2017 ◽  
Author(s):  
Derek Burton ◽  
Margaret Burton
Keyword(s):  
Carbon Dioxide ◽  
Blood Cells ◽  
Venous Return ◽  
White Blood Cells ◽  
Nutrient Transport ◽  
Blood System ◽  
Fluid Component ◽  
Nucleated Red Blood Cells ◽  
Ventral Aorta ◽  
Osmotic Effects

The blood system transports nutrients, oxygen, carbon dioxide and nitrogenous wastes; other functions include defence. Fish have a closed, single circulation in which blood is pumped by a contractile heart via a ventral aorta to the gills, then via the dorsal aorta to vessels supplying the tissues and organs, with a venous return to the heart. Large venous sinuses occur in elasmobranchs. Air-breathing fish have modifications of the circulation. Complex networks of narrow blood vessels can occur as red patches, retia, maximizing transfer of nutrients, oxygen or heat. Most fish have nucleated red blood cells (erythrocytes) with haemoglobin. The types of white blood cells (leucocytes) are similar to those of other vertebrates but there are thrombocytes rather than platelets. Nutrient transport is in the plasma, the fluid component of the blood, which may also carry antifreeze agents and molecules (e.g. urea in elasmobranchs) which counteract deleterious osmotic effects

In Vitro Assay for Single-cell Characterization of Impaired Deformability in Red Blood Cells under Recurrent Episodes of Hypoxia

Lab on a Chip ◽  
2021 ◽  
Author(s):  
YUHAO QIANG ◽  
Jia Liu ◽  
Ming Dao ◽  
E Du
Keyword(s):  
Shear Stress ◽  
Red Blood Cells ◽  
Single Cell ◽  
Blood Cells ◽  
Blood Circulation ◽  
In Vitro Assay ◽  
Vitro Assay ◽  
Cyclic Shear

Red blood cells (RBCs) are subjected to recurrent changes in shear stress and oxygen tension during blood circulation. The cyclic shear stress has been identified as an important factor that...

Carbon dioxide transport in crustal magmatic systems

2011 ◽  
Vol 307 (3-4) ◽  
pp. 470-478 ◽  
Author(s):  
Shumpei Yoshimura ◽  
Michihiko Nakamura
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Transport
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