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 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 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.

Prolactin inhibits corticoid-induced differentiation of active Na+ transport across cultured frog tadpole skin

1995 ◽  
Vol 269 (5) ◽  
pp. C1326-C1331 ◽  
Author(s):  
M. Takada ◽  
H. Yai ◽  
K. Takayama-Arita
Keyword(s):  
Acetylcholine Receptor ◽  
Inhibitory Action ◽  
Blood Group Antigen ◽  
The Other ◽  
Basal Cells ◽  
Na Transport ◽  
Adult Type ◽  
Frog Tadpole ◽  
Antigen A ◽  
Tadpole Skin

Active Na+ transport differentiates in larval bullfrog skin cultured with corticoids. After 2 wk in culture, the epidermis became positive against human blood group antigen A, the marker for the adult-type cells of the epidermis, but was negative to the antibody against the acetylcholine receptor, the marker for the larval-type epidermis. Amiloride (10(-5) M) did not inhibit the differentiation of active Na+ transport. On the other hand, in skin cultured with prolactin (2 micrograms/ml), the epidermis remained negative against antigen A and positive against acetylcholine receptor, and the differentiation of active Na+ transport was inhibited. Thyroid hormone did not antagonize the inhibitory action of prolactin on this transport differentiation. Prolactin affected the basal cells of the larval epidermis and inhibited development of corticoid-induced adult features in the epidermis.

scholarly journals Molecular Modelling of Human Red Blood Cell Pyruvate Kinase: Structural Implications of a Novel G1091 to A Mutation Causing Severe Nonspherocytic Hemolytic Anemia

Blood ◽  
1997 ◽  
Vol 90 (12) ◽  
pp. 4987-4995 ◽  
Author(s):  
Wouter W. van Solinge ◽  
Rob J. Kraaijenhagen ◽  
Gert Rijksen ◽  
Richard van Wijk ◽  
Bjarne B. Stoffer ◽  
...  
Keyword(s):  
Blood Cell ◽  
Pyruvate Kinase ◽  
Hemolytic Anemia ◽  
Red Blood Cell ◽  
Molecular Modelling ◽  
Human Liver ◽  
The Other ◽  
Salt Bridges ◽  
Compound Heterozygotes ◽  
Allosteric Properties

Abstract We present a novel G1091 to A mutation in the human liver and red blood cell (RBC) pyruvate kinase (PK) gene causing severe hemolytic anemia. In two families, three children were severely PK-deficient compound heterozygotes exhibiting the G1091 to A mutation and a common G1529 to A mutation on the other allele. In one family, the mother, a G1091 to A heterozygote, later had a second baby with a new husband, also a G1091 to A carrier. The baby was homozygous for the G1091 to A mutation and died 6 weeks after birth from severe hemolysis. Both mutant alleles were expressed at the RNA level. The G1091 to A mutation results in the substitution of a conserved glycine by an aspartate in domain A of RBC PK, whereas the G1529 to A mutation leads to the substitution of a conserved arginine residue with glutamine in the C-domain. Molecular modelling of human RBC PK, based on the crystal structure of cat muscle PK, shows that both mutations are located outside the catalytic site at the interface of domains A and C. The mutations are likely to disrupt the critical conformation of the interface by introducing alternative salt bridges. In this way the Gly364 to Asp and Arg510 to Gln substitutions may cause PK deficiency by influencing the allosteric properties of the enzyme.

Studies in Red Blood Cell Preservation 1. Effect of the Other Formed Elements

Vox Sanguinis ◽  
1990 ◽  
Vol 58 (2) ◽  
pp. 85-89 ◽  
Author(s):  
T. J. Greenwalt ◽  
C. Zehner Sostok ◽  
U. J. Dumaswala
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
The Other ◽  
Cell Preservation

Effects of Fluvastatin Treatment on Red Blood Cell Na+ Transport Systems in Hypercholesterolemic Subjects

2000 ◽  
Vol 35 (3) ◽  
pp. 376-382 ◽  
Author(s):  
Antonino Saitta ◽  
Maria Castaldo ◽  
Adriana Sardo ◽  
Michele N. Saitta ◽  
Maurizio Cinquegrani ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Transport Systems ◽  
Na Transport ◽  
Hypercholesterolemic Subjects ◽  
Fluvastatin Treatment

Studies in Red Blood Cell Preservation - 1. Effect of the Other Formed Elements

Vox Sanguinis ◽  
1990 ◽  
Vol 58 (2) ◽  
pp. 85-89
Author(s):  
C. Zehner Sostok ◽  
U.J. Dumaswala ◽  
T.J. Greenwalt
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
The Other ◽  
Cell Preservation

scholarly journals IV. On the structure of the red blood-corpuscle of oviparous vertebrata

1869 ◽  
Vol 17 ◽  
pp. 346-350
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
The Other ◽  
Red Cell ◽  
Blood Corpuscle ◽  
Fundamental Distinction ◽  
Long Time ◽  
History Of

The red blood-cell has been perhaps more frequently and fully examined than any other animal structure; certainly none has evoked such various and even contradictory opinions of its nature. But without attempting here any history of these, it may be shortly said that amongst the conclusions now, and for a long time past, generally accepted, a chief one is that a fundamental distinction exists between the red corpuscle of Mammalia and that of the other vertebrate classes—that the red cell of the oviparous vertebrata possesses a nucleus which is not to be found in the corpuscle of the other class. This great distinction between the classes has of late years been over and over again laid down in the strongest and most unqualified terms. But I venture to ask for a still further examination of this important subject.

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