scholarly journals Side-dependent effects of internal versus external Na and K on ouabain binding to reconstituted human red blood cell ghosts.

1976 ◽  
Vol 67 (5) ◽  
pp. 497-525 ◽  
Author(s):  
H H Bodemann ◽  
J F Hoffman
Keyword(s):  
Blood Cell ◽  
Binding Site ◽  
Red Blood Cell ◽  
Red Cell ◽  
Ouabain Binding ◽  
Binding Properties ◽  
Conformational States ◽  
Binding Rate ◽  
Lack Of Control

The side-dependent effects of internal and external Na and K on the ouabain binding rate, as promoted by inside MgATP, has been evaluated utilizing reconstituted human red blood cell ghosts. Such ghost systems provide the situation where [Na]i, [K]i, [Na]o, and [K]o can each be varied under conditions in which the others are either absent or fixed at constant concentrations. It was found that, in the presence of Ko, increasing either [Na]i or [K]i resulted in decreasing the rate at which ouabain was bound. Changes in [Na]i or [K]i in the absence of Ko were without effect on the ouabain binding rate. Thus, the ouabain binding rate was found to vary inversely with the rate of Na:K and K:K exchange but was independent of the rate of Na:Na exchange. The effect of Ko in antagonizing ouabain binding, as well as the influence of Nao on this interaction, were found to require the presence of either Nai or Ki. The results are interpreted in terms of a model relating the availability of the ouabain binding site to different conformational states of the pump complex. Differences were observed in the ouabain binding properties of red cell ghosts compared to microsomal preparations but it is not known whether the basis for the differences resides in the different preparations studied or in the lack of control of sidedness in the microsomal systems.

scholarly journals Effects of Mg and Ca on the side dependencies of Na and K on ouabain binding to red blood cell ghosts and the control of Na transport by internal Mg.

1976 ◽  
Vol 67 (5) ◽  
pp. 547-561 ◽  
Author(s):  
H H Bodemann ◽  
J F Hoffman
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Inhibitory Action ◽  
External Surface ◽  
The Other ◽  
Na Transport ◽  
Ouabain Binding ◽  
Conformational States ◽  
Binding Rate ◽  
Relative Affinity

The effect of alteration in the concentration of internal Mg on the rate of ouabain binding to reconstituted human red blood cell ghosts has been evaluated as well as the effect of Mgi on Na:Na compared to Na:K exchange. It was found that the dependence of the rate of ATP-promoted ouabain binding on the combined presence of Nai and Ko which occurs at high [Mg]i is lost when the concentration of Mgi is lowered. The sensitivity of the external surface for Ko is also changed since Ko can now inhibit the ouabain binding rate in the absence of Nai; on the other hand Nao at low [Mg]i can stimulate ouabain binding indicating that the relative affinity of the outside surface for Nao has either increased or that for Ko has decreased or both. Thus the effects of changes in [Mg]i result in a change in the side-dependent actions of Na and K and emphasize the possible difficulties of interpreting results obtained on systems lacking sidedness. Mgi was found to be required for Pi-promoted ouabain binding and that the inhibitory action of Nai increased as [Mg]i was increased. In addition, Ca was found to be most effective in inhibiting the rate of ATP-promoted ouabain binding when Na and K were present together than when either was present alone. Na:K exchange was found to be more sensitive to the concentration of Mgi than Na:Na exchange; at low [Mg]i Na:K exchange could be stimulated without changing the extent of Na:Na exchange. These results are consistent with the idea that conformational states of the pump complex are directly influenced by [Mg]i.

scholarly journals Comparison of the side-dependent effects of Na and K on orthophosphate-, UTP-, and ATP-promoted ouabain binding to reconstituted human red blood cell ghosts.

1976 ◽  
Vol 67 (5) ◽  
pp. 527-545 ◽  
Author(s):  
H H Bodemann ◽  
J F Hoffman
Keyword(s):  
Blood Cell ◽  
Adenosine Triphosphate ◽  
Mechanism Of Action ◽  
Red Blood Cell ◽  
Ouabain Binding ◽  
Uridine Triphosphate ◽  
Binding Rate ◽  
External K

This paper is concerned with analyzing the sidedness of action of various determinants which alter the rate of ouabain binding to human red blood cell ghosts. Thus, ouabain binding promoted by orthophosphate (Pi) and its inhibition by Na are shown to be due to inside Pi and inside Na. External K inhibits Pi-promoted ouabain binding and Nao acts to decrease the effectiveness of Ko. Similarly, inside uridine triphosphate (UTPi) stimulates the rate of ouabain binding which can be antagonized by either Nai or Ko acting alone. The actions of Nai and Ko are different when ouabain binding is promoted by Pi and UTPi compared to inside adenosine triphosphate (ATPi). With ATPi, the ouabain binding rate is only affected when Nai and Ko are both present. Possible differences in the mechanism of action of K and Na on Pi-and UTP-promoted binding are discussed in the light of their sidedness of action.

Advantages of Larger Volume, Less Frequent Intrauterine Red Blood Cell Transfusions for Maternal Red Cell Alloimmunization

1996 ◽  
Vol 13 (01) ◽  
pp. 27-33 ◽  
Author(s):  
Steven Inglis ◽  
Andrzej Lysikiewicz ◽  
Amy Sonnenblick ◽  
Jane Streltzoff ◽  
James Bussel ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Red Cell ◽  
Red Blood Cell Transfusions

Footstrike is the major cause of hemolysis during running

2003 ◽  
Vol 94 (1) ◽  
pp. 38-42 ◽  
Author(s):  
R. D. Telford ◽  
G. J. Sly ◽  
A. G. Hahn ◽  
R. B. Cunningham ◽  
C. Bryant ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Blood Cell ◽  
Red Blood Cell ◽  
Random Order ◽  
Peak Oxygen Uptake ◽  
Red Cell ◽  
Free Hemoglobin ◽  
Serum Haptoglobin ◽  
Total Hemoglobin ◽  
Exercise Induced

There is a wide body of literature reporting red cell hemolysis as occurring after various forms of exercise. Whereas the trauma associated with footstrike is thought to be the major cause of hemolysis after running, its significance compared with hemolysis that results from other circulatory stresses on the red blood cell has not been thoroughly addressed. To investigate the significance of footstrike, we measured the degree of hemolysis after 1 h of running. To control for the potential effects of oxidative and circulatory stresses on the red blood cell, the same subjects cycled for 1 h at equivalent oxygen uptake. Our subjects were 10 male triathletes, who each completed two separate 1-h sessions of running and cycling at 75% peak oxygen uptake, which were performed in random order 1 wk apart. Plasma free hemoglobin and serum haptoglobin concentrations were measured as indicators of hemolysis. We also measured methemoglobin as a percentage of total hemoglobin immediately postexercise as an indicator of red cell oxidative stress. Plasma free hemoglobin increased after both running ( P < 0.01) and cycling ( P < 0.01), but the increase was fourfold greater after running ( P < 0.01). This was reflected by a significant fall in haptoglobin 1 h after the running trials, whereas no significant changes occurred after cycling at any sample point. Methemoglobin increased twofold after both running and cycling ( P < 0.01), with no significant differences between modes of exercise. The present data indicate that, whereas general circulatory trauma to the red blood cells associated with 1 h of exercise at 75% maximal oxygen uptake may result in some exercise-induced hemolysis, footstrike is the major contributor to hemolysis during running.

scholarly journals Increased Ca++, Mg++, and Na+ + K+ ATPase activities in erythrocytes of sickle cell anemia

Blood ◽  
1982 ◽  
Vol 60 (6) ◽  
pp. 1332-1336 ◽  
Author(s):  
MG Luthra ◽  
DA Sears
Keyword(s):  
Enzyme Activity ◽  
Blood Cell ◽  
Atpase Activity ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Red Blood Cell ◽  
Calcium Binding ◽  
Red Cells ◽  
Low Density ◽  
Red Cell

Abstract To determine whether diminished activity of the Ca++ extrusion pump could account for the high levels of red blood cell (RBC) Ca++ in sickle cell anemia (SS), we measured calmodulin-sensitive Ca++ ATPase activity in normal and SS RBC. Hemolysates prepared with saponin were compared, since such preparations expressed maximum ATPase activities, exceeding isolated membranes or reconstituted systems of membranes plus cytosol, SS RBC hemolysates had greater Ca++ ATPase activity than normal hemolysates; they exhibited higher Mg++ and Na+ + K+ ATPase activities as well. Assays on density (age) fractions of SS and normal red cells demonstrated that all ATPase activities were highest in low density (young) cells, and activities in SS red cells exceeded those in normals in all fractions studied. Thus, when studied under conditions that maximize enzyme activity, Ca++ ATPase activity, like Mg++ and Na+ + K+ ATPase, is actually increased in SS RBC, probably due to the young red cell population present. The elevated Ca++ levels in these cells are more likely due to an increased Ca++ leak or abnormal calcium binding than to defective extrusion by the ATPase pump.

scholarly journals Red blood cell alloimmunisation and autoimmunisation in transfusion dependent beta thalassemics from Southern India

2015 ◽  
Vol 05 (03) ◽  
pp. 004-008
Author(s):  
Mohammed Saleem E. K. ◽  
Soundarya Mahalingam ◽  
Shamee Shastri ◽  
Kamalakshi G. Bhat
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Beta Thalassemia ◽  
Red Cell ◽  
Transfusion Therapy ◽  
Female Ratio ◽  
Antibody Screening ◽  
Cell Antigen ◽  
Low Ionic Strength ◽  
Male To Female

AbstractThe development of red blood cell (RBC) isoimmunization with alloantibodies and autoantibodies complicate transfusion therapy in multiply transfused thalassemia patients. We conducted a study to analyse the frequency in our population. Clinical and antibody profile from 55 multiply transfused thalassemic patients who were receiving transfusions were collected and analyzed prospectively. A commercially available 3 cell antigen panel was used for the antibody screening procedure. If antibody screening with the 3-cell antigen panel was positive, an extended 11-cell antigen panel was used for antibody identification in LISS (Low Ionic Strength Solution). All patients received blood matched for only ABO and Rh (D) antigens. A total of 55 transfusion dependent â thalassemics were included in this study out of which 30 (54.55%) were males and 25(45.45%) females with a male to female ratio of 1.2: 1. Frequency of red cell alloimmunization in this study was found to be 1.8%. None of the patients developed red cell autoimmunization. The alloantibody identified in the the patient who developed alloimmunisation was was anti-K. In conclusion, the transfusion of matched blood is essential for chronically transfused beta thalassemia patients in order to avoid alloimmunization.

scholarly journals RED CELL STROMA PROTEIN RICH IN VITAMIN B12 DURING ACTIVE REGENERATION

1955 ◽  
Vol 102 (6) ◽  
pp. 725-731 ◽  
Author(s):  
G. H. Whipple ◽  
F. S. Robscheit-Robbins ◽  
W. F. Bale
Keyword(s):  
Blood Cell ◽  
Vitamin B12 ◽  
Pernicious Anemia ◽  
Red Blood Cell ◽  
Red Cells ◽  
Cell Regeneration ◽  
Red Cell ◽  
Low Levels ◽  
Active Regeneration ◽  
Protein Rich

During active blood regeneration in anemia in dogs an increase occurs in the stroma protein of the red cells. When vitamin B12 with radioactive cobalt is given at the start of this blood regeneration one finds concentration of labeled B12 in the stroma protein but not in the hemoglobin. After the acute phase of red cell regeneration is ended the concentration of B12 in stroma protein falls rapidly to very low levels within 2 weeks. Subsequent episodes of red blood cell regeneration seems not to cause remobilization of radioactive cobalt into red cells from other body stores. It appears that the vitamin B12 is a factor of importance in the first steps of stroma protein formation in the first few days of the life of the red cell in the dog. This response in dogs and the response in pernicious anemia to vitamin B12 may have some points in common. Distribution of the B12-radioactive cobalt in the organs and tissues at autopsy has been recorded. Some very suggestive localizations were noted and some variation 1 week and 7 weeks after B12 injections. Radioactive cobalt escapes in the urine during the weeks following B12 injections.

scholarly journals [3H]Ouabain binding and Na+, K+-ATPase in resealed human red cell ghosts.

1983 ◽  
Vol 81 (3) ◽  
pp. 401-420 ◽  
Author(s):  
D G Shoemaker ◽  
P K Lauf
Keyword(s):  
Adenylate Kinase ◽  
Kinase Activity ◽  
Kinase Inhibitor ◽  
Adenosine Diphosphate ◽  
Red Cell ◽  
Ouabain Binding ◽  
Intracellular Magnesium ◽  
High Affinity ◽  
Binding Rate ◽  
High Affinity Binding Site

The interaction of the cardiac glycoside [3H]ouabain with the Na+, K+ pump of resealed human erythrocyte ghosts was investigated. Binding of [3H]ouabain to high intracellular Na+ ghosts was studied in high extracellular Na+ media, a condition determined to produce maximal ouabain binding rates. Simultaneous examination of both the number of ouabain molecules bound per ghost and the corresponding inhibition of the Na+, K+-ATPase revealed that one molecule of [3H]ouabain inhibited one Na+, K+-ATPase complex. Intracellular magnesium or magnesium plus inorganic phosphate produced the lowest ouabain binding rate. Support of ouabain binding by adenosine diphosphate (ADP) was negligible, provided synthesis of adenosine triphosphate (ATP) through the residual adenylate kinase activity was prevented by the adenylate kinase inhibitor Ap5A. Uridine 5'-triphosphate (UTP) alone did not support ouabain binding after inhibition of the endogenous nucleoside diphosphokinase by trypan blue and depletion of residual ATP by the incorporation of hexokinase and glucose. ATP acting solely at the high-affinity binding site of the Na+, K+ pump (Km approximately 1 microM) promoted maximal [3H]ouabain binding rates. Failure of 5'-adenylyl-beta-gamma-imidophosphate (AMP-PNP) to stimulate significantly the rate of ouabain binding suggests that phosphorylation of the pump was required to expose the ouabain receptor.

scholarly journals Plasmodium falciparum erythrocyte-binding antigen 175 triggers a biophysical change in the red blood cell that facilitates invasion

2017 ◽  
Vol 114 (16) ◽  
pp. 4225-4230 ◽  
Author(s):  
Marion Koch ◽  
Katherine E. Wright ◽  
Oliver Otto ◽  
Maik Herbig ◽  
Nichole D. Salinas ◽  
...  
Keyword(s):  
Cell Surface ◽  
Blood Cell ◽  
Signaling Pathways ◽  
Red Blood Cell ◽  
Malaria Parasite ◽  
Red Cell ◽  
Biophysical Properties ◽  
Parasite Invasion ◽  
Bending Modulus ◽  
Erythrocyte Binding

Invasion of the red blood cell (RBC) by the Plasmodium parasite defines the start of malaria disease pathogenesis. To date, experimental investigations into invasion have focused predominantly on the role of parasite adhesins or signaling pathways and the identity of binding receptors on the red cell surface. A potential role for signaling pathways within the erythrocyte, which might alter red cell biophysical properties to facilitate invasion, has largely been ignored. The parasite erythrocyte-binding antigen 175 (EBA175), a protein required for entry in most parasite strains, plays a key role by binding to glycophorin A (GPA) on the red cell surface, although the function of this binding interaction is unknown. Here, using real-time deformability cytometry and flicker spectroscopy to define biophysical properties of the erythrocyte, we show that EBA175 binding to GPA leads to an increase in the cytoskeletal tension of the red cell and a reduction in the bending modulus of the cell’s membrane. We isolate the changes in the cytoskeleton and membrane and show that reduction in the bending modulus is directly correlated with parasite invasion efficiency. These data strongly imply that the malaria parasite primes the erythrocyte surface through its binding antigens, altering the biophysical nature of the target cell and thus reducing a critical energy barrier to invasion. This finding would constitute a major change in our concept of malaria parasite invasion, suggesting it is, in fact, a balance between parasite and host cell physical forces working together to facilitate entry.

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