KCl Cotransport in HbAA and HbSS Red Cells: Activation by Intracellular Acidity and Disappearance During Maturation

AbstractAbnormal activity of red cell KCl cotransport (KCC) is involved in pathogenesis of sickle cell anaemia (SCA). KCC-mediated solute loss causes shrinkage, concentrates HbS, and promotes HbS polymerisation. Red cell KCC also responds to various stimuli including pH, volume, urea, and oxygen tension, and regulation involves protein phosphorylation. The main aim of this study was to investigate the role of the WNK/SPAK/OSR1 pathway in sickle cells. The pan WNK inhibitor WNK463 stimulated KCC with an EC50 of 10.9 ± 1.1 nM and 7.9 ± 1.2 nM in sickle and normal red cells, respectively. SPAK/OSR1 inhibitors had little effect. The action of WNK463 was not additive with other kinase inhibitors (staurosporine and N-ethylmaleimide). Its effects were largely abrogated by pre-treatment with the phosphatase inhibitor calyculin A. WNK463 also reduced the effects of physiological KCC stimuli (pH, volume, urea) and abolished any response of KCC to changes in oxygen tension. Finally, although protein kinases have been implicated in regulation of phosphatidylserine exposure, WNK463 had no effect. Findings indicate a predominant role for WNKs in control of KCC in sickle cells but an apparent absence of downstream involvement of SPAK/OSR1. A more complete understanding of the mechanisms will inform pathogenesis whilst manipulation of WNK activity represents a potential therapeutic approach.

Download Full-text

Contamination of salvaged maternal blood by amniotic fluid and fetal red cells during elective Caesarean section

Yearbook of Anesthesiology and Pain Management ◽

10.1016/s1073-5437(08)79057-0 ◽

2009 ◽

Vol 2009 ◽

pp. 250-251

Author(s):

D.H. Chestnut

Keyword(s):

Caesarean Section ◽

Amniotic Fluid ◽

Elective Caesarean Section ◽

Maternal Blood ◽

Red Cells

Download Full-text

Differential Outcomes for Long Term ex vivo Lung Perfusion in a Porcine Model - With or without Red Cells?

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0035-1544536 ◽

2015 ◽

Vol 63 (S 01) ◽

Author(s):

W. Sommer ◽

M. Avsar ◽

J. Salman ◽

C. Kühn ◽

I. Tudorache ◽

...

Keyword(s):

Porcine Model ◽

Ex Vivo ◽

Lung Perfusion ◽

Red Cells ◽

Ex Vivo Lung Perfusion ◽

Differential Outcomes

Download Full-text

Liquoid Induced Stasis and the Generalized Shwartzman Reaction

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646840 ◽

1979 ◽

Vol 41 (04) ◽

pp. 804-810 ◽

Cited By ~ 1

Author(s):

Knut Nordstoga

Keyword(s):

Red Cells ◽

Renal Lesions ◽

Intravenous Injections ◽

Shwartzman Reaction ◽

Glomerular Capillaries

SummaryThe composition of the occlusive material within dilated glomerular capillaries, following intravenous injections of Liquoid in blue foxes, was studied electron microscopically; it was found that it mainly consisted of a debris in which disintegrated red cells constituted the major component. Damaged platelets and necrotic endothelial remnants were other components. These observations were interpreted as a result of glomerular stasis, and it was concluded that stasis in glomerular capillaries is a basic event in the development of the renal lesions accompanying the generalized Shwartzman reaction.

Download Full-text

Receptor Mediated Binding of the Fibrinolytic Components, Plasminogen and Urokinase, to Peripheral Blood Cells

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646019 ◽

1987 ◽

Vol 58 (03) ◽

pp. 936-942 ◽

Cited By ~ 96

Author(s):

Lindsey A Miles ◽

Edward F Plow

Keyword(s):

T Cells ◽

B Cell ◽

Peripheral Blood ◽

Binding Sites ◽

Blood Cells ◽

High Capacity ◽

Red Cells ◽

Peripheral Blood Cells ◽

Cellular Functions ◽

Fibrinolytic Proteins

SummaryGlu-plasminogen binds to platelets; the monocytoid line, U937, and the human fetal fibroblast line, GM1380 bind both plasminogen and its activator, urokinase. This study assesses the interaction of these fibrinolytic proteins with circulating human blood cells. Plasminogen bound minimally to red cells but bound saturably and reversibly to monocytes, granulocytes and lymphocytes with apparent Kd values of 0.9-1.4 μM. The interactions were of high capacity with 1.6 to 49 × 105 sites/cell and involved the lysine binding sites of plasminogen. Both T cells and non-rosetting lymphocytes and two B cell lines saturably bound plasminogen. Urokinase bound saturably to gianulocytes, monocytes, non-rosetting lymphocytes and a B cell line, but minimally to T cells, platelets and red cells. Therefore, plasminogen binding sites of high capacity, of similar affinities, and with common recognition specificities are expressed by many peripheral blood cells. Urokinase receptors are also widely distributed, but less so than plasminogen binding sites. The binding ol plasminogen and/ or urokinase to these cells may lead to generation of cell- associated proteolytic activity which contributes to a variety of cellular functions.

Download Full-text

Antithrombin Activity of Intact Human Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651361 ◽

1975 ◽

Vol 34 (01) ◽

pp. 115-126 ◽

Cited By ~ 3

Author(s):

Kiyoake Watanabe ◽

Francis C Chao ◽

James L Tullis

Keyword(s):

Antithrombin Iii ◽

Human Platelets ◽

Significant Loss ◽

Red Cells ◽

Antithrombin Activity ◽

Α2 Macroglobulin ◽

Rapid Reaction ◽

Pre Treatment ◽

Different Characteristics

SummaryAntithrombin activity has been identified in intact washed human platelets. An apparent activity was demonstrated at platelet concentrations above 0.31 × 109/ml, when platelet suspensions were incubated with 2.0 NIH units/ml of thrombin. Neither red cells nor white cells revealed antithrombin activity. No significant loss of the platelet antithrombin activity was observed after ten successive washings or after treatment of platelets with antibodies to antithrombin III or α2-macroglobulin. Almost the same amount of antithrombin activity as normal platelets was demonstrated in the platelets from an afibrinogenemic patient. Pre-treatment of platelets with trypsin, papain, and neuroaminidase reduced the activity significantly, whereas lipase was without effect. The platelet antithrombin reacted with thrombin in less than 3 seconds, and this rapid reaction of platelet antithrombin was different from that of plasma antithrombin III or fibrinogen. The thrombin-like clotting activity of ancrod was inhibited by fibrinogen but not platelets. Also, unlike plasma antithrombin III or fibrinogen, brief exposure to heat (56° C or 60° C) reduced considerable amounts of platelet antithrombin activity. These results suggest that platelets possess a specific antithrombin with different characteristics from other known antithrombins.

Download Full-text

In Vitro Assay of Platelet Adhesiveness with Washed and Tanned Human Red Cells

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651281 ◽

1968 ◽

Vol 20 (03/04) ◽

pp. 384-396 ◽

Cited By ~ 1

Author(s):

G Zbinden ◽

S Tomlin

Keyword(s):

Platelet Adhesion ◽

Sodium Citrate ◽

Blood Platelets ◽

In Vitro Assay ◽

Red Cells ◽

Platelet Adhesiveness ◽

Vitro Assay ◽

In Vitro System ◽

Human Red Cells

SummaryAn in vitro system is described in which adhesion of blood platelets to washed and tannic acid-treated red cells was assayed quantitatively by microscopic observation. ADP, epinephrine and TAME produced a reversible increase in platelet adhesiveness which was antagonized by AMP. With Evans blue, polyanetholsulfonate, phthalanilide NSC 38280, thrombin and heparin at concentrations above 1-4 u/ml the increase was irreversible. The ADP-induced increase in adhesiveness was inhibited by sodium citrate, EDTA, AMP, ATP and N-ethylmaleimide. EDTA, AMP and the SH-blocker N-ethylmaleimide also reduced spontaneous platelet adhesion to red cells. No significant effects were observed with adenosine, phenprocoumon, 5-HT, phthalanilide NSC 57155, various estrogens, progestogens and fatty acids, acetylsalicylic acid and similarly acting agents, hydroxylamine, glucose and KCN. The method may be useful for the screening of thrombogenic and antithrombotic properties of drugs.

Download Full-text

LACK OF EFFECT OF CORTICOSTEROIDS ON THE IN VIVO DISAPPEARANCE OF SULFHYDRYL-INHIBITED AND ANTIBODY-COATED ERYTHROCYTES

Acta Endocrinologica ◽

10.1530/acta.0.047s028 ◽

1964 ◽

Vol 47 (3_Suppl) ◽

pp. S28-S36

Author(s):

Kailash N. Agarwal

Keyword(s):

Red Cells ◽

List Type ◽

Red Cell

ABSTRACT Red cells were incubated in vitro with sulfhydryl inhibitors and Rhantibody with and without prior incubation with prednisolone-hemisuccinate. These erythrocytes were labelled with Cr51 and P32 and their disappearance in vivo after autotransfusion was measured. Prior incubation with prednisolone-hemisuccinate had no effect on the rate of red cell disappearance. The disappearance of the cells was shown to take place without appreciable intravascular destruction.

Download Full-text

STUDIES ON HAEMORRHAGIC LIPAEMIA IN RATS WITH PARTICULAR REFERENCES TO THE EFFECT OF HYPOPHYSECTOMY

Acta Endocrinologica ◽

10.1530/acta.0.xxxiv0473 ◽

1960 ◽

Vol XXXIV (III) ◽

pp. 473-482 ◽

Cited By ~ 7

Author(s):

Sven Punsar ◽

Gottfried Härtel ◽

Antti Louhija ◽

Olli P. Heinonen

Keyword(s):

Serum Cholesterol ◽

Red Cells ◽

Similar Increase ◽

Hypophysectomized Rats

ABSTRACT Repeated bleeding in rats caused a definite increase in the serum cholesterol and phospholipid concentrations and a visible lipaemia. The development of lipaemia could be inhibited by injections of red cells in amounts sufficient to prevent the anaemia. The injection of serum corresponding in amount to that withdrawn had no effect in this respect. In hypophysectomized rats, the bleeding caused a similar increase in the serum cholesterol and phospholipid levels but no visible lipaemia.

Download Full-text