Ouabain inhibition of the sodium-potassium pump: estimation of ED50 in different types of human leucocytes in vitro

B Møller, Allan Vaag, Torben Johansen

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

1. We examined the effect of ouabain on the Na(+)-K+ pump of intact mononuclear leucocytes and polymorphonuclear leucocytes by using the radioactive potassium analogue, 86rubidium, as a tracer and measuring the cellular uptake of K+ (86Rb+). Na(+)-K+ pump activity was determined as the cellular uptake of K+ (86Rb+) that is sensitive to ouabain, 10(-5) mol l-1. 2. Dose-response curves for inhibition of the Na(+)-K+ pump were obtained after exposure of the cells to various concentrations of ouabain for 2.5 h when the level of pump inhibition was considered to be at steady state. 3. The ED50 of ouabain for the effect on the Na(+)-K+ pump was estimated to be 3 X 10(-9) mol l-1 in the absence of potassium. In the presence of potassium, 3 and 6.5 X 10(-3) mol l-1, it was increased by factors of 10 and 45 respectively. In the presence of potassium, 4 X 10(-3) mol l-1, the ED50 was similar but somewhat higher when determined in an artificial medium (Ringer solution) than when determined in autologous plasma. 4. The ED50 values observed in the present study were very similar to KD values reported in the literature on ligand binding of tritiated ouabain to the same types of human leucocytes.
OriginalsprogEngelsk
TidsskriftBritish Journal of Clinical Pharmacology
Vol/bind29
Udgave nummer1
Sider (fra-til)93-100
Antal sider8
ISSN0306-5251
StatusUdgivet - 1990

Fingeraftryk

Sodium-Potassium-Exchanging ATPase
Ouabain
Potassium
Neutrophils
In Vitro Techniques
Ligands

Citer dette

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title = "Ouabain inhibition of the sodium-potassium pump: estimation of ED50 in different types of human leucocytes in vitro",
abstract = "1. We examined the effect of ouabain on the Na(+)-K+ pump of intact mononuclear leucocytes and polymorphonuclear leucocytes by using the radioactive potassium analogue, 86rubidium, as a tracer and measuring the cellular uptake of K+ (86Rb+). Na(+)-K+ pump activity was determined as the cellular uptake of K+ (86Rb+) that is sensitive to ouabain, 10(-5) mol l-1. 2. Dose-response curves for inhibition of the Na(+)-K+ pump were obtained after exposure of the cells to various concentrations of ouabain for 2.5 h when the level of pump inhibition was considered to be at steady state. 3. The ED50 of ouabain for the effect on the Na(+)-K+ pump was estimated to be 3 X 10(-9) mol l-1 in the absence of potassium. In the presence of potassium, 3 and 6.5 X 10(-3) mol l-1, it was increased by factors of 10 and 45 respectively. In the presence of potassium, 4 X 10(-3) mol l-1, the ED50 was similar but somewhat higher when determined in an artificial medium (Ringer solution) than when determined in autologous plasma. 4. The ED50 values observed in the present study were very similar to KD values reported in the literature on ligand binding of tritiated ouabain to the same types of human leucocytes.",
keywords = "Biological Transport, Active, Humans, Leukocytes, Lymphocytes, Monocytes, Neutrophils, Ouabain, Potassium, Rubidium Radioisotopes, Sodium",
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Ouabain inhibition of the sodium-potassium pump: estimation of ED50 in different types of human leucocytes in vitro. / Møller, B; Vaag, Allan; Johansen, Torben.

I: British Journal of Clinical Pharmacology, Bind 29, Nr. 1, 1990, s. 93-100.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Ouabain inhibition of the sodium-potassium pump: estimation of ED50 in different types of human leucocytes in vitro

AU - Møller, B

AU - Vaag, Allan

AU - Johansen, Torben

PY - 1990

Y1 - 1990

N2 - 1. We examined the effect of ouabain on the Na(+)-K+ pump of intact mononuclear leucocytes and polymorphonuclear leucocytes by using the radioactive potassium analogue, 86rubidium, as a tracer and measuring the cellular uptake of K+ (86Rb+). Na(+)-K+ pump activity was determined as the cellular uptake of K+ (86Rb+) that is sensitive to ouabain, 10(-5) mol l-1. 2. Dose-response curves for inhibition of the Na(+)-K+ pump were obtained after exposure of the cells to various concentrations of ouabain for 2.5 h when the level of pump inhibition was considered to be at steady state. 3. The ED50 of ouabain for the effect on the Na(+)-K+ pump was estimated to be 3 X 10(-9) mol l-1 in the absence of potassium. In the presence of potassium, 3 and 6.5 X 10(-3) mol l-1, it was increased by factors of 10 and 45 respectively. In the presence of potassium, 4 X 10(-3) mol l-1, the ED50 was similar but somewhat higher when determined in an artificial medium (Ringer solution) than when determined in autologous plasma. 4. The ED50 values observed in the present study were very similar to KD values reported in the literature on ligand binding of tritiated ouabain to the same types of human leucocytes.

AB - 1. We examined the effect of ouabain on the Na(+)-K+ pump of intact mononuclear leucocytes and polymorphonuclear leucocytes by using the radioactive potassium analogue, 86rubidium, as a tracer and measuring the cellular uptake of K+ (86Rb+). Na(+)-K+ pump activity was determined as the cellular uptake of K+ (86Rb+) that is sensitive to ouabain, 10(-5) mol l-1. 2. Dose-response curves for inhibition of the Na(+)-K+ pump were obtained after exposure of the cells to various concentrations of ouabain for 2.5 h when the level of pump inhibition was considered to be at steady state. 3. The ED50 of ouabain for the effect on the Na(+)-K+ pump was estimated to be 3 X 10(-9) mol l-1 in the absence of potassium. In the presence of potassium, 3 and 6.5 X 10(-3) mol l-1, it was increased by factors of 10 and 45 respectively. In the presence of potassium, 4 X 10(-3) mol l-1, the ED50 was similar but somewhat higher when determined in an artificial medium (Ringer solution) than when determined in autologous plasma. 4. The ED50 values observed in the present study were very similar to KD values reported in the literature on ligand binding of tritiated ouabain to the same types of human leucocytes.

KW - Biological Transport, Active

KW - Humans

KW - Leukocytes

KW - Lymphocytes

KW - Monocytes

KW - Neutrophils

KW - Ouabain

KW - Potassium

KW - Rubidium Radioisotopes

KW - Sodium

M3 - Journal article

C2 - 2297465

VL - 29

SP - 93

EP - 100

JO - British Journal of Clinical Pharmacology

JF - British Journal of Clinical Pharmacology

SN - 0306-5251

IS - 1

ER -