scholarly journals The Effect of Enhanced Fibrinolytic Activity on the Red Cell Membrane Transport

1977 ◽  
Author(s):  
S.B. Ulutin ◽  
N. B. Emekli ◽  
T. U. Yardimici
Keyword(s):  
Active Transport ◽  
Fibrinolytic Activity ◽  
Time Course ◽  
Degradation Products ◽  
Human Subjects ◽  
Red Cells ◽  
Fibrinolytic System ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Before And After

In dogs and in human subjects, using hepatic vein catheterization before and after the activation of the fibrinolytic system, the blood samples were obtained and the red cell amino acid transport was investigated. The time course accumulation of radioactive histidine in isolated red cells was followed together with the measurements of the fibrinolytic activity.A decrease in the active transport of histidine was observed in the red cells after the stimulation of the fibrinolytic system. Also a correlation between the decrease of active transport and the increase of fibrin-fibrinogen degradation products was seen.

scholarly journals Partial spectrin deficiency in hereditary pyropoikilocytosis

Blood ◽  
1986 ◽  
Vol 67 (4) ◽  
pp. 919-924 ◽  
Author(s):  
TL Coetzer ◽  
J Palek
Keyword(s):  
Degradation Products ◽  
Membrane Skeleton ◽  
Red Cells ◽  
Proteolytic Degradation ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Erythroid Precursor ◽  
Single Defect

Abstract Hereditary pyropoikilocytosis (HPP) is a severe hemolytic anemia in which an instability of the red cell membrane skeleton has been correlated with structural and functional defects of spectrin. We now report that 13 unrelated HPP subjects have approximately 30% less spectrin than normal as evidenced by a decreased spectrin/band 3 ratio. We also examine the role of spectrin degradation as an underlying cause of this partial spectrin deficiency. Our studies demonstrate that the reduced spectrin content of HPP red cells remains constant during in vivo aging of the cells in the peripheral blood, as well as during in vitro incubation. Furthermore, immunoblotting experiments using an affinity-purified antispectrin antibody indicate that there is no loss of spectrin during membrane preparation and also that neither whole HPP red cells nor ghosts nor cytosol contains any abnormal spectrin degradation products. These data suggest that spectrin is not degraded and that it is stable on the membrane of the circulating HPP red cell. In contrast, however, incubation of free spectrin with a lysate of nucleated erythroid precursor cells indicates that HPP alpha I/46 spectrin, but not HPP alpha I/74 spectrin, is more susceptible to proteolytic degradation than a control. These data imply that the decreased spectrin content of HPP is not due to a single defect but that a more complex mechanism is involved. In HPP Sp alpha I/46 subjects, an increased proteolytic degradation in bone marrow erythroid precursors of cytosolic spectrin, prior to its assembly on the membrane, could contribute toward the partial spectrin deficiency.

scholarly journals Partial spectrin deficiency in hereditary pyropoikilocytosis

Blood ◽  
1986 ◽  
Vol 67 (4) ◽  
pp. 919-924
Author(s):  
TL Coetzer ◽  
J Palek
Keyword(s):  
Degradation Products ◽  
Membrane Skeleton ◽  
Red Cells ◽  
Proteolytic Degradation ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Erythroid Precursor ◽  
Single Defect

Hereditary pyropoikilocytosis (HPP) is a severe hemolytic anemia in which an instability of the red cell membrane skeleton has been correlated with structural and functional defects of spectrin. We now report that 13 unrelated HPP subjects have approximately 30% less spectrin than normal as evidenced by a decreased spectrin/band 3 ratio. We also examine the role of spectrin degradation as an underlying cause of this partial spectrin deficiency. Our studies demonstrate that the reduced spectrin content of HPP red cells remains constant during in vivo aging of the cells in the peripheral blood, as well as during in vitro incubation. Furthermore, immunoblotting experiments using an affinity-purified antispectrin antibody indicate that there is no loss of spectrin during membrane preparation and also that neither whole HPP red cells nor ghosts nor cytosol contains any abnormal spectrin degradation products. These data suggest that spectrin is not degraded and that it is stable on the membrane of the circulating HPP red cell. In contrast, however, incubation of free spectrin with a lysate of nucleated erythroid precursor cells indicates that HPP alpha I/46 spectrin, but not HPP alpha I/74 spectrin, is more susceptible to proteolytic degradation than a control. These data imply that the decreased spectrin content of HPP is not due to a single defect but that a more complex mechanism is involved. In HPP Sp alpha I/46 subjects, an increased proteolytic degradation in bone marrow erythroid precursors of cytosolic spectrin, prior to its assembly on the membrane, could contribute toward the partial spectrin deficiency.

scholarly journals Red Cell Membrane Permeability Deduced from Bulk Diffusion Coefficients

1974 ◽  
Vol 64 (6) ◽  
pp. 706-729 ◽  
Author(s):  
W. R. Redwood ◽  
E. Rall ◽  
W. Perl
Keyword(s):  
Cell Membrane ◽  
Membrane Permeability ◽  
Diffusion Coefficients ◽  
Bulk Diffusion ◽  
Red Cells ◽  
Cell Membrane Permeability ◽  
Red Cell ◽  
Cell Column ◽  
Red Cell Membrane ◽  
One Dimensional

The permeability coefficients of dog red cell membrane to tritiated water and to a series of[14C]amides have been deduced from bulk diffusion measurements through a "tissue" composed of packed red cells. Red cells were packed by centrifugation inside polyethylene tubing. The red cell column was pulsed at one end with radiolabeled solute and diffusion was allowed to proceed for several hours. The distribution of radioactivity along the red cell column was measured by sequential slicing and counting, and the diffusion coefficient was determined by a simple plotting technique, assuming a one-dimensional diffusional model. In order to derive the red cell membrane permeability coefficient from the bulk diffusion coefficient, the red cells were assumed to be packed in a regular manner approximating closely spaced parallelopipeds. The local steady-state diffusional flux was idealized as a one-dimensional intracellular pathway in parallel with a one-dimensional extracellular pathway with solute exchange occurring within the series pathway and between the pathways. The diffusion coefficients in the intracellular and extracellular pathways were estimated from bulk diffusion measurements through concentrated hemoglobin solutions and plasma, respectively; while the volume of the extracellular pathway was determined using radiolabeled sucrose. The membrane permeability coefficients were in satisfactory agreement with the data of Sha'afi, R. I., C. M. Gary-Bobo, and A. K. Solomon (1971. J. Gen. Physiol. 58:238) obtained by a rapid-reaction technique. The method is simple and particularly well suited for rapidly permeating solutes.

Time course of exchanges between red cells and extracellular fluid during CO2 uptake

1975 ◽  
Vol 38 (4) ◽  
pp. 710-718 ◽  
Author(s):  
R. E. Forster ◽  
E. D. Crandall
Keyword(s):  
Carbonic Anhydrase ◽  
Time Course ◽  
Extracellular Fluid ◽  
Extracellular Ph ◽  
Co2 Uptake ◽  
Sudden Increase ◽  
Red Cell ◽  
Ph Change ◽  
Red Cell Membrane

A stopped-flow rapid-reaction apparatus was used to follow the time course of extracellular pH in a human red cell suspension following a sudden increase in PCO2. The extracellular pH change was slow (t1/2 similar to 3.5 s) considering the presence of carbonic anhydrase in the cells. When carbonic anhydrase was added to the extracellular fluid, the half-time was reduced to less than 20 ms. The explanation for these phenomena is that the equilibration of H+ across the red cell membrane is rate-limited by the uncatalyzed reaction CO2 plus H2O formed from H2CO3 outside the cells. A theoretical model was developed which successfully reproduced the experimental results. When the model was used to simulate CO2 exchange in vivo, it was determined that blood PCO2 and pH require long times (greater than 50 s) to approach equilibrium between cells and plasma after leaving an exchange capillary. We conclude that cell-plasma equilibrium may never be reached in vivo, and that in vitro measurements of these quantities may not represent their true values at the site of sampling.

scholarly journals Kinetics and stoichiometry of Na-dependent Li transport in human red blood cells.

1978 ◽  
Vol 72 (2) ◽  
pp. 249-265 ◽  
Author(s):  
B Sarkadi ◽  
J K Alifimoff ◽  
R B Gunn ◽  
D C Tosteson
Keyword(s):  
Transport System ◽  
Red Cells ◽  
Normal Male ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Human Red Blood Cells ◽  
Na Efflux ◽  
Tightly Coupled ◽  
Male Subjects ◽  
Human Red Cells

This paper describes the kinetics and stoichiometry of a tightly coupled Na-Li exchange transport system in human red cells. The system is inhibited by phloretin and furosemide but not by ouabain. Li influx by this system increases and saturates with increasing concentrations of external Li and internal Na and is inhibited competitively by external Na. Comparable functions relate Li efflux and Na efflux to internal and external Li and Na concentrations. Analysis of these relations yields the following values for the ion concentrations required to half-maximally activate the transport system: internal Na and Li 9.0 and 0.5 mM, respectively, external Na and Li 25 and 1.5 mM, respectively. The system performs a 1:1 exchange of Na and Li moving in opposite directions across the red cell membrane. We found no evidence for a simultaneous transport of more than one Na and Li by the system. The maximum transport rate of Na-dependent Li transport varied between 0.1 and 0.37 mmol/(liter of cells X h) in the red cells of the five normal male subjects studied. No significant variations between individual subjects were observed for bicarbonate-stimulated Li transport and for the residual Li fluxes which occur in the absence of bicarbonate and in the presence of ouabain plus phloretin.

scholarly journals Genetic variants of human red-cell membrane sialoglycoprotein β. Study of the alterations occurring in the sialoglycoprotein-β gene

1988 ◽  
Vol 250 (2) ◽  
pp. 407-414 ◽  
Author(s):  
M J Tanner ◽  
S High ◽  
P G Martin ◽  
D J Anstee ◽  
P A Judson ◽  
...  
Keyword(s):  
Genetic Variants ◽  
Southern Blotting ◽  
Protein Product ◽  
Red Cells ◽  
The Other ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Initiation Of Translation ◽  
Beta Gene ◽  
Human Red Cell Membrane

We have studied the DNA of individuals who express an altered sialoglycoprotein beta on their red cells by using Southern blotting with sialoglycoprotein-beta cDNA probes. Individuals of the Leach phenotype do not express any beta (sialoglycoprotein beta) or gamma (sialoglycoprotein gamma) on their red cells, and we show that about 7 kb of DNA, including the 3′ end of the beta gene, is deleted in this DNA. Any protein product of this gene is likely to lack the membrane-associating domain of beta. We have also examined the DNA of two types of other individuals (Yus-type and Gerbich-type) who have red cells that lack beta and gamma, but contain abnormal sialoglycoproteins related to beta. These two types of DNA contain different internal deletions of about 6 kb in the beta gene. We suggest that these deletions result from the presence of two different sets of internal homology in the beta gene, and on this basis we propose structures for the abnormal Yus-type and Gerbich-type sialoglycoproteins which are consistent with the other evidence that is available. We provide evidence that beta and gamma are products of the same gene and suggest a possible mechanism for the origin of gamma based on leaky initiation of translation of beta mRNA.

scholarly journals The relationship between in vivo generated hemoglobin skeletal protein complex and increased red cell membrane rigidity

Blood ◽  
1988 ◽  
Vol 71 (5) ◽  
pp. 1427-1431 ◽  
Author(s):  
N Fortier ◽  
LM Snyder ◽  
F Garver ◽  
C Kiefer ◽  
J McKenney ◽  
...  
Keyword(s):  
Protein Complex ◽  
Sodium Dodecyl ◽  
Red Cells ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Cellular Dehydration ◽  
Thalassemia Minor ◽  
Membrane Rigidity

Abstract In vitro induced oxidative damage to normal human RBCs has previously been shown to result in increased membrane rigidity as a consequence of the generation of a protein complex between hemoglobin and spectrin. In order to determine if in vivo generated hemoglobin-spectrin complexes may play a role in increased membrane rigidity of certain pathologic red cells, we measured both these parameters in membranes prepared from hereditary xerocytosis (Hx), sickle cell disease (Sc), and red cells from thalassemia minor (beta thal). Membranes were prepared from density-fractionated red cells, and membrane deformability was measured using an ektacytometer. Hemoglobin-spectrin complex was determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel analysis, as well as by Western blot analysis using a monoclonal antibody against the beta- subunit of hemoglobin. For these three types of pathologic red cells, progressive cellular dehydration was associated with increased membrane rigidity and increased content of hemoglobin-spectrin complex. Moreover, the increase in membrane rigidity appeared to be directly related to the quantity of hemoglobin-spectrin complex associated with the membrane. Our findings imply that hemoglobin-spectrin complex is generated in vivo, and this in turn results in increased membrane rigidity of certain pathologic red cells. The data further suggest that oxidative crosslinking may play an important role in the pathophysiology of certain red cell disorders.

Effects of exercise and conditioning on clotting and fibrinolytic activity in men

1987 ◽  
Vol 62 (4) ◽  
pp. 1416-1421 ◽  
Author(s):  
E. W. Ferguson ◽  
L. L. Bernier ◽  
G. R. Banta ◽  
J. Yu-Yahiro ◽  
E. B. Schoomaker
Keyword(s):  
Fibrinolytic Activity ◽  
Blood Clotting ◽  
Degradation Products ◽  
Clot Lysis ◽  
Plasma Clot ◽  
Fitness Program ◽  
Fibrin Degradation Products ◽  
Before And After ◽  
Plasmin Inhibitor ◽  
Sedentary Subjects

Sixty healthy men in three physical fitness categories (sedentary, on no organized fitness program; joggers, running 5–15 miles/wk; and marathoners, running greater than 50 miles/wk) were evaluated for changes in blood clotting and fibrinolytic activity before and after maximum exercise on a treadmill according to the Bruce protocol. The rate of blood clotting, as measured by prothrombin times, partial thromboplastin times and thrombin times, was accelerated by exercise (all P less than 0.005). The ability of euglobulin clots and plasma clots to lyse incorporated 125I-fibrin, termed 125I-euglobulin clot lysis (IEL) and 125I-plasma clot lysis (IPCL), were used as indexes of fibrinolytic activity. Marathoners had greater increases in fibrinolytic activity with exercise (76% compared with 63% for joggers and 55% for sedentary subjects by IEL; 427% compared with 418% for joggers and 309% for sedentary subjects by IPCL; all P less than 0.05). Fibrin degradation products increased with exercise (P less than 0.005 for the total group of 60 subjects). The absolute concentrations of alpha 2-plasmin inhibitor, alpha 2-macroglobulin, and antithrombin III increased with exercise (all P less than 0.005), but when concentrations were corrected for acute shifts of plasma water during exercise, the quantity of these inhibitors actually decreased (all P less than 0.005). The changes in clotting assays with exercise were not significantly correlated with changes in whole blood lactate, blood pyruvate, or rectal temperatures. Fibrinolytic assays before and after exercise correlated poorly to moderately with blood lactates (IEL: r = 0.441 and r = 0.425, respectively; IPCL: r = 0.294 and r = 0.544, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Inhibition of malarial parasite invasion by monoclonal antibodies against glycophorin A correlates with reduction in red cell membrane deformability

Blood ◽  
1989 ◽  
Vol 74 (5) ◽  
pp. 1836-1843 ◽  
Author(s):  
G Pasvol ◽  
JA Chasis ◽  
N Mohandas ◽  
DJ Anstee ◽  
MJ Tanner ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Cell Membrane ◽  
Red Cells ◽  
Malarial Parasite ◽  
Glycophorin A ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Parasite Invasion ◽  
Surface Molecules ◽  
Fab Fragments

Abstract The effect of well-characterized monoclonal antibodies to red cell surface molecules on the invasion of human red cells by the malarial parasites Plasmodium falciparum and Plasmodium knowlesi was examined. Antibodies to glycophorin A (GP alpha) inhibit invasion for both parasite species, and this is highly correlated with the degree to which they decrease red cell membrane deformability as measured by ektacytometry. This effect on rigidity and invasion was also seen with monovalent Fab fragments. The closer the antibody binding site was to the membrane bilayer, the greater was its effect on inducing membrane rigidity and decreasing parasite invasion. Antibodies to the Wright determinant in particular were the most inhibitory. This differential effect of the various antibodies was not correlated with their binding affinities or the number of sites bound per cell. Antibodies to surface molecules other than GP alpha were without effect. A novel mechanism is described whereby monoclonal antibodies and their Fab fragments directed at determinants on the external surface of red cells might act to inhibit invasion by malarial parasites by altering membrane material properties.

scholarly journals Antisickling effect of tellurite: a potent membrane-acting agent in vitro

Blood ◽  
1984 ◽  
Vol 64 (1) ◽  
pp. 305-307 ◽  
Author(s):  
T Asakura ◽  
Y Shibutani ◽  
MP Reilly ◽  
RH DeMeio
Keyword(s):  
Hemoglobin Concentration ◽  
Inhibitory Effect ◽  
Red Cells ◽  
Cell Swelling ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Potassium Tellurite ◽  
New Type ◽  
Acting Agent

Abstract Potassium tellurite (K2TeO3) was found to be a potent antisickling agent that inhibited red cell sickling at concentrations less than 10 mumol/L. The inhibitory effect depended on the incubation time, with the effect increasing with longer incubation periods. Because tellurite causes swelling of red cells, and because the antisickling effect of tellurite correlated with the degree of red cell swelling, the antisickling effect of tellurite is assumed to be due to the decreased mean cell hemoglobin concentration. Swelling of red cells by tellurite was accelerated by the addition of reduced glutathione. Tellurite appears to be a new type of antisickling agent that interacts with the red cell membrane.

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