scholarly journals Studies of High Potassium and Low Potassium Sheep Erythrocyte Membrane Sodium-Adenosine Triphosphatase

1973 ◽  
Vol 248 (5) ◽  
pp. 1772-1777 ◽  
Author(s):  
Rhoda Blostein ◽  
Emerson S. Whittington
Keyword(s):  
Erythrocyte Membrane ◽  
Adenosine Triphosphatase ◽  
Sheep Erythrocyte ◽  
High Potassium ◽  
Low Potassium

scholarly journals Changes from High Potassium (HK) to Low Potassium (LK) in Bovine Red Cells

1972 ◽  
Vol 59 (3) ◽  
pp. 270-284 ◽  
Author(s):  
Yedy Israel ◽  
Alain Macdonald ◽  
Jaime Bernstein ◽  
Eduardo Rosenmann
Keyword(s):  
Adenosine Triphosphatase ◽  
Sodium Content ◽  
Red Cells ◽  
Red Cell ◽  
Transport Capacity ◽  
High Potassium ◽  
A Value ◽  
Low Potassium ◽  
Newborn Calves ◽  
Time Required

Red cells of newborn calves contain 105–110 mmole K+ and 1–5 mmole Na+ per liter of cells. As the animals age the K+ content decreases to a value of 25–30 mmole/liter of cells after about 60 days. At approximately the same time, the sodium content reaches a value of 60–70 mmole/liter. The time required for half change (t½) is 35–37 days for both Na+ and K+. The activity of (Na + K)-adenosine triphosphatase (ATPase) and the influx of K42 and Rb86 into the red cells are high at birth and are reduced to 5 and 15% of their original values, respectively, in mature animals. t½ for both is of the order of 30–35 days. The membrane Mg-ATPase activity is also high at birth and is reduced with a t½ of 28–32 days to a final value of about 20% of its activity at birth. Separation of red cells according to their age showed that, in animals at the age of transition, newly formed red cells contain a higher K/Na ratio and a higher active transport capacity than older red cells of the same animal. It is suggested that the changes observed are a reflection of the average age of the red cell population as the animal grows.

Changes in Erythrocyte Membrane Ouabain-Sensitive Adenosine Triphosphatase after Renal Transplantation

1975 ◽  
Vol 48 (3) ◽  
pp. 239-242 ◽  
Author(s):  
C. H. Cole ◽  
R. Maletz
Keyword(s):  
Renal Transplantation ◽  
Atpase Activity ◽  
Erythrocyte Membrane ◽  
Adenosine Triphosphatase ◽  
Inorganic Phosphorus ◽  
Erythrocyte Membranes ◽  
Healthy Controls ◽  
Intracellular Electrolytes ◽  
Transplant Patients ◽  
The Mean

1. Intracellular electrolytes, and erythrocyte membrane adenosine triphosphatase (ATPase) activity, was studied in twenty patients after renal transplantation. 2. The mean ouabain-sensitive ATPase activity in the erythrocyte membranes of the transplant patients was 122 nmol of inorganic phosphorus (Pi) h−1 mg of tissue−1 (sem 14), compared with 62 nmol of Pi h−1 mg of tissue−1 (sem 8) in a group of paired, healthy controls. 3. The increase in ouabain-sensitive ATPase was most marked in the 4 months after transplantation. However, a significant increase in ouabain-sensitive ATPase persisted for more than 8 months after transplantation. 4. This increase in ouabain-sensitive ATPase was associated with a decrease in intracellular sodium in the erythrocytes of the transplant patients.

Voltage-activated cation permeability in high-potassium but not low-potassium red blood cells

1990 ◽  
Vol 258 (6) ◽  
pp. C1169-C1172 ◽  
Author(s):  
J. A. Halperin ◽  
C. Brugnara ◽  
T. Van Ha ◽  
D. C. Tosteson
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Dielectric Breakdown ◽  
Cation Transport ◽  
Membrane Component ◽  
Transport Pathway ◽  
High Potassium ◽  
Human Red Blood Cells ◽  
Cation Permeability ◽  
Low Potassium

We have recently reported that voltage-activated fluxes of Na, K, and Ca occur in human red blood cells [J.A. Halperin, C. Brugnara, M. Tosteson, T. Van Ha, and D. C. Tosteson. Am. J. Physiol. 257 (Cell Physiol. 26): C986-C996, 1989]. The cation permeability increases progressively as the membrane potential becomes more inside positive above +20 mV. In this paper we show that this effect also occurs in high-potassium (HK), but not in low-potassium (LK), sheep and dog red blood cells. This result suggests that the voltage-activated cation transport pathway is not the result of nonspecific dielectric breakdown of the lipid bilayer but, rather, relates to some membrane component, presumably a protein, that is expressed in HK human and sheep but not in LK sheep and dog red blood cells.

Effect of Electroconvulsive Therapy on Erythrocyte Adenosine Triphosphatase Activity in Depressive Illness

1980 ◽  
Vol 137 (4) ◽  
pp. 343-345 ◽  
Author(s):  
L. J. Whalley ◽  
M. Scott ◽  
H. W. Reading ◽  
J. E. Christie
Keyword(s):  
Atpase Activity ◽  
Erythrocyte Membrane ◽  
Electroconvulsive Therapy ◽  
Healthy Subjects ◽  
Adenosine Triphosphatase ◽  
Depressive Illness ◽  
Slight Reduction ◽  
Acute Effects ◽  
Adenosine Triphosphatase Activity ◽  
Depressed Patients

SummaryErythrocyte membrane adenosine triphosphatase activities were examined in twelve unipolar depressed patients receiving ECT. Eleven patients undergoing diagnostic cystoscopy served as controls for the acute effects of anaesthesia, and sixteen healthy subjects served as non-depressed controls. The unipolar depressed patients had a slight reduction in their (Na++K+)-ATPase activity but effective ECT treatment was not associated with any increase in this activity. This approach is unlikely to cast further light on the membrane phenomenology of depressive illness.

Decreased Ouabain-Sensitive Adenosine Triphosphatase Activity in the Erythrocyte Membrane of Patients with Chronic Renal Disease

1973 ◽  
Vol 45 (6) ◽  
pp. 775-784 ◽  
Author(s):  
C. H. Cole
Keyword(s):  
Renal Disease ◽  
Erythrocyte Membrane ◽  
Adenosine Triphosphatase ◽  
Chronic Renal Disease ◽  
Sodium Concentration ◽  
Erythrocyte Membranes ◽  
General Medical Ward ◽  
Adenosine Triphosphatase Activity ◽  
Average Decrease ◽  
Erythrocyte Sodium

1. Ouabain-sensitive ATPase (adenosine triphosphatase) activity was measured in the erythrocyte membranes of twenty patients with chronic renal disease. Decreased activity was found in nineteen of the twenty patients. The average decrease was 38%. 2. In three patients erythrocyte sodium concentration exceeded 9·5 mmol/l of RBC and these patients had the most marked decreases in ouabain-sensitive ATPase activity. 3. By contrast, in only two of 100 patients admitted to a general medical ward was erythrocyte sodium concentration greater than 9.5 mmol/l of RBC. 4. Ouabain-insensitive and calcium-activated components of erythrocyte membrane ATPase were unaffected by chronic renal disease.

scholarly journals Bone Morphogenetic Protein-6 Promotes Cerebellar Granule Neurons Survival by Activation of the MEK/ERK/CREB Pathway

2009 ◽  
Vol 20 (24) ◽  
pp. 5051-5063 ◽  
Author(s):  
Bruna Barneda-Zahonero ◽  
Alfredo Miñano-Molina ◽  
Nahuai Badiola ◽  
Rut Fadó ◽  
Xavier Xifró ◽  
...  
Keyword(s):  
Bone Morphogenetic Proteins ◽  
Granule Cells ◽  
Cerebellar Granule Cells ◽  
Neuroprotective Effect ◽  
High Potassium ◽  
Cerebellar Granule ◽  
Low Potassium ◽  
Creb Pathway

Bone morphogenetic proteins (BMPs) have been implicated in the generation and postnatal differentiation of cerebellar granule cells (CGCs). Here, we examined the eventual role of BMPs on the survival of these neurons. Lack of depolarization causes CGC death by apoptosis in vivo, a phenomenon that is mimicked in vitro by deprivation of high potassium in cultured CGCs. We have found that BMP-6, but not BMP-7, is able to block low potassium–mediated apoptosis in CGCs. The neuroprotective effect of BMP-6 is not accompanied by an increase of Smad translocation to the nucleus, suggesting that the canonical pathway is not involved. By contrast, activation of the MEK/ERK/CREB pathway by BMP-6 is necessary for its neuroprotective effect, which involves inhibition of caspase activity and an increase in Bcl-2 protein levels. Other pathways involved in the regulation of CGC survival, such as the c-Jun terminal kinase and the phosphatidylinositol 3-kinase (PI3K)-Akt/PKB, were not affected by BMP-6. Moreover, failure of BMP-7 to activate the MEK/ERK/CREB pathway could explain its inability to protect CGCs from low potassium–mediated apoptosis. Thus, this study demonstrates that BMP-6 acting through the noncanonical MEK/ERK/CREB pathway plays a crucial role on CGC survival.

Sign in / Sign up

Export Citation Format

Share Document