Cow red blood cells. II. Stimulation of bovine red cell glycolysis by plasma

1979 ◽  
Vol 236 (5) ◽  
pp. C262-C267 ◽  
Author(s):  
M. J. Seider ◽  
H. D. Kim

Cow red cell glycolysis, which can be stimulated by a variety of purines and pyrimidines, was also found to be elevated by its own plasma. Dialyzed or charcoal-treated plasma could no longer stimulate glycolysis, suggesting that the stimulating factors may be purines or pyrimidines. Determination of purines or pyrimidines in plasma revealed the presence of xanthine (0.31 muM), hypoxanthine (0.60 muM), and adenosine (0.05 muM), as well as unknown compounds. A physiologic level of hypoxanthine, with or without xanthine and adenosine approximating their concentrations in plasma, resulted in the stimulation of cow red cell glycolytic rate by 16% (P less than 0.01). These findings suggest that plasma-borne purines may act on cow red cells in concert with as yet unidentified factors. Moreover, exchanging calf and cow plasmas produced no stimulatory effect on either calf or cow red cell glycolysis, suggesting that a) calf red cells lack some of the cellular components that respond to this stimulator and, b) only cow plasma contains this specific stimulator. In other species, including dog, cat, rabbit, rat, guinea pig, and human, stimulation of glycolysis by plasma was not observed.

1996 ◽  
Vol 271 (4) ◽  
pp. R973-R981 ◽  
Author(s):  
S. Glombitza ◽  
S. Dragon ◽  
M. Berghammer ◽  
M. Pannermayr ◽  
R. Baumann

In late chick embryos, coordinate activation of red cell carbonic anhydrase II (CAII) and 2,3-diphosphoglycerate (2,3-DPG) synthesis is initiated by hypoxia. The effects are mediated by unidentified hormonal effectors resident in chick plasma. In the present investigation, we have analyzed the effect of adenosine receptor stimulation on embryonic red cell CAII and 2,3-DPG synthesis. We find that primitive and definitive embryonic red blood cells from chick have an A2a adenosine receptor. Stimulation of the receptor with metabolically stable adenosine analogues causes a large increase of red cell adenosine 3',5'-cyclic monophosphate (cAMP) and subsequent activation of red cell CAII and 2,3-DPG production in definitive red blood cells and of CAII synthesis in primitive red blood cells. Direct stimulation of adenylyl cyclase with forskolin has the same effect. Analysis of red cell protein pattern after labeling with [35S]methionine shows that stimulation of red cell cAMP levels activates synthesis of several other proteins aside from CAII. Presence of actinomycin D inhibits cAMP-dependent changes of protein synthesis, indicating that cAMP-dependent transcriptional activation is required. In contrast to the stable adenosine receptor analogues, adenosine itself was a very weak agonist, unless its metabolism was significantly inhibited. Thus, besides adenosine, other effectors of the adenylyl cyclase system are likely to be involved in the O2 pressure-dependent regulation of red cell metabolism in late development of avian embryos.


Blood ◽  
1959 ◽  
Vol 14 (4) ◽  
pp. 399-408 ◽  
Author(s):  
WILLIAM H. CROSBY

Abstract During all the stages of a red cell’s life the normal spleen exerts a normal function. Eight of these functions have been considered: (1) erythropoiesis; (2) an effect upon red cell production; (3) an effect upon maturation of the red cell surface; (4) the reservoir function; (5) the "culling function"; (6) iron turnover and storage; (7) the "pitting function"; (8) destruction of old red cells.


1922 ◽  
Vol 4 (4) ◽  
pp. 403-409 ◽  
Author(s):  
Calvin B. Coulter

1. The addition of blood serum displaces the optimum for agglutination of red blood cells in a salt-free medium to the reaction characteristic of flocculation of the serum euglobulin. 2. This effect is not due merely to a mechanical entanglement of the cells by the precipitating euglobulin, since at reactions at which the latter is soluble it protects the cells from the agglutination which occurs in its absence. 3. A combination of some sort appears therefore to take place between sheep cells and sheep, rabbit, and guinea pig serum euglobulin, and involves a condensation of the serum protein upon the surface of the red cell. 4. At the optimal point for agglutination of persensitized cells both mid- and end-piece of complement combine with the cells. 5. Agglutination is closely related to an optimal H ion concentration in the suspending fluid, and probably of the cell membrane, and not to a definite reaction in the interior of the cell.


1989 ◽  
Vol 203 ◽  
pp. 381-400 ◽  
Author(s):  
D. Halpern ◽  
T. W. Secomb

An analysis is presented of the mechanics of red blood cells flowing in very narrow tubes. Mammalian red cells are highly flexible, but their deformations satisfy two significant constraints. They must deform at constant volume, because the contents of the cell are incompressible, and also at nearly constant surface area, because the red cell membrane strongly resists dilation. Consequently, there exists a minimal tube diameter below which passage of intact cells is not possible. A cell in a tube with this diameter has its critical shape: a cylinder with hemispherical ends. Here, flow of red cells in tubes with near-minimal diameters is analysed using lubrication theory. When the tube diameter is slightly larger than the minimal value, the cell shape is close to its shape in the critical case. However, the rear end of the cell becomes flattened and then concave with a relatively small further increase in the diameter. The changes in cell shape and the resulting rheological parameters are analysed using matched asymptotic expansions for the high-velocity limit and using numerical solutions. Predictions of rheological parameters are also obtained using the assumption that the cell is effectively rigid with its critical shape, yielding very similar results. A rapid decrease in the apparent viscosity of red cell suspensions with increasing tube diameter is predicted over the range of diameters considered. The red cell velocity is found to exceed the mean bulk velocity by an amount that increases with increasing tube diameter.


Author(s):  
Fay M. John ◽  
G. C. Forrest

Phospholipids from the red cells of 85 children, both normal and belonging to various clinical groups, have been extracted and subjected to silica gel chromatography. The several phospholipids have been quantitated. The results have not proved to be useful in diagnosis and hence do not confirm earlier reports. The problems associated with analysis of phospholipids by this type of method are discussed.


2021 ◽  
Vol 12 ◽  
Author(s):  
Perumal Thiagarajan ◽  
Charles J. Parker ◽  
Josef T. Prchal

Normal human red blood cells have an average life span of about 120 days in the circulation after which they are engulfed by macrophages. This is an extremely efficient process as macrophages phagocytose about 5 million erythrocytes every second without any significant release of hemoglobin in the circulation. Despite large number of investigations, the precise molecular mechanism by which macrophages recognize senescent red blood cells for clearance remains elusive. Red cells undergo several physicochemical changes as they age in the circulation. Several of these changes have been proposed as a recognition tag for macrophages. Most prevalent hypotheses for red cell clearance mechanism(s) are expression of neoantigens on red cell surface, exposure phosphatidylserine and decreased deformability. While there is some correlation between these changes with aging their causal role for red cell clearance has not been established. Despite plethora of investigations, we still have incomplete understanding of the molecular details of red cell clearance. In this review, we have reviewed the recent data on clearance of senescent red cells. We anticipate recent progresses in in vivo red cell labeling and the explosion of modern proteomic techniques will, in near future, facilitate our understanding of red cell senescence and their destruction.


Blood ◽  
1961 ◽  
Vol 18 (3) ◽  
pp. 349-363 ◽  
Author(s):  
STANLEY YACHNIN ◽  
FRANK H. GARDNER

Abstract Agglutinins for various artificially altered red blood cells belong to the class of 19S macroglobulins, which migrate electrophoretically as fast gamma or slow beta globulins. The agglutinin activity of serum for altered red cells is readily destroyed by sulfhydryl compounds. Hemolysins for altered red cells are not readily recoverable from serum fractions prepared by starch block electrophoresis or density gradient ultracentrifugation, but, when present, are found to have the same properties. This information lends credence to the concept of these serum factors as examples of "natural antibody," although the stimulus to their formation is not understood. The sera from patients with various types of hemolytic anemias and various dysproteinemias including macroglobulinemia were found to contain normal amounts of altered red cell agglutinins and hemolysins. The sera from three patients with congenital agammaglobulinemia were studied. Two of these sera contained agglutinins and hemolysins for altered red blood cells, as well as isohemolysins and isoagglutinins. The significance of this finding is discussed. The "T" agglutinin and the agglutinin for periodate-treated red cells, both of which are macroglobulins, have been shown by other workers to be absent from newborn sera. Their inability to cross the placenta can be explained by their large size.


Blood ◽  
1983 ◽  
Vol 62 (1) ◽  
pp. 214-217 ◽  
Author(s):  
PA Aarts ◽  
PA Bolhuis ◽  
KS Sakariassen ◽  
RM Heethaar ◽  
JJ Sixma

Abstract The hematocrit is one of the main factors influencing platelet adherence to the vessel wall. Raising the hematocrit causes an increase of platelet accumulation of about an order of magnitude. Our studies concern the role of red cell size. We have studied this effect using an annular perfusion chamber, according to Baumgartner, with human umbilical arteries and a steady-flow system. Normal human red blood cells (MCV 95 cu mu) increased platelet adherence sevenfold, as the hematocrit increases from 0 to 0.6. Small erythrocytes from goats (MCV 25 cu mu) caused no increment in adherence in the same hematocrit range. Rabbit erythrocytes (MCV 70 cu mu) caused an intermediate increase in adherence. Red blood cells from newborns (MCV 110–130 cu mu) caused a larger increase in platelet adherence than normal red cells at hematocrit 0.4. These results were further confirmed with large red blood cells from two patients. Experiments with small red cells (MCV 70 cu mu) of patients with iron deficiency showed that platelet adherence was similar to normal red cells, provided the red cell diameter was normal. Small red blood cells of a patient with sideroblastic anemia caused decreased adherence. These data indicate that red cell size is of major importance for platelet adherence. Red cell diameter is more important than average volume. However, for size differences in the human range, the hematocrit remains the dominant parameter.


2000 ◽  
Vol 89 (3) ◽  
pp. 1198-1204 ◽  
Author(s):  
Robert L. Conhaim ◽  
Lance A. Rodenkirch ◽  
Kal E. Watson ◽  
Bruce A. Harms

High lung inflation pressures compress alveolar septal capillaries, impede red cell transit, and interfere with oxygenation. However, recently introduced acellular hemoglobin solutions may enter compressed lung capillaries more easily than red blood cells. To test this hypothesis, we perfused isolated rat lungs with fluorescently labeled diaspirin cross-linked hemoglobin (DCLHb; 10%) and/ or autologous red cells (hematocrit, 20). Septal capillaries were compressed by setting lung inflation pressure above vascular pressures (zone 1). Examination by confocal microscopy showed that DCLHb was distributed throughout alveolar septa. Furthermore, this distribution was not affected by adding red blood cells to the perfusate. We estimated the maximum acellular hemoglobin mass within septa to be equivalent to that of 15 red blood cells. By comparison, we found an average of 2.7 ± 4.6 red cells per septum in zone 1. These values increased to 30.4 ± 25.8 and 50.4 ± 22.1 cells per septum in zones 2 and 3, respectively. We conclude that perfusion in zone 1 with a 10% acellular hemoglobin solution may increase the hemoglobin concentration per septum up to fivefold compared with red cell perfusion.


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