John S. Willis

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1. Measurements were made of the binding of [(3)H]ouabain to a variety of cell types.2. Two components of binding could usually be distinguished: a component that saturated at low glycoside concentrations and a component that increased up to the highest ouabain concentrations examined.3. Detailed studies with HeLa cells and kidney slices from guinea-pigs(More)
1. Na-K pumps of rodent red cells reveal variations among species in terms of kinetic properties such as ouabain sensitivity, Na/K coupling and temperature sensitivity and variations within an individual organism related to such physiological challenges as K deficiency, calorie deficiency and seasonal changes in temperature. 2. Passive Na entry among(More)
1. The ATP concentration of intact, cold-tolerant (ground squirrel) red cells and cold-sensitive (guinea-pig and human) red cells was monitored by use of the firefly tail, luciferin-luciferase assay. ATP kinetics of the pump in intact red blood cells was investigated by altering cell [ATP] by progressive depletion of ATP in the presence of 2-deoxy-D-glucose(More)
Unidirectional, ouabain-insensitive K+ influx rose steeply with warming at temperatures above 37°C in guinea pig erythrocytes incubated in isotonic medium. The only component of ouabain-insensitive K+ influx to show the same steep rise was K-Cl cotransport (Q10 of 10 between 37 and 41°C); Na-K-Cl cotransport remained constant or declined and residual K+(More)
Although several studies have suggested that the reduced activity of the Na+-K+ pump during starvation is a source of energy conservation, the hypothesis has not been tested in intact cells, nor has the contribution of passive permeability been considered in a controlled animal study. In this study three components of K+ influx (Na+-K+ pump = ouabain(More)
1. Membrane transport of Na ions was investigated in red blood cells of bears by methods of measurement of unidirectional isotopic fluxes. 2. Like red blood cells of dogs, bear red cells contain a high Na concentration and low concentrations of K and ATP. 3. As in dog red cells, Na efflux from bear cells was not inhibited by ouabain but was activated by the(More)