Phytohemagglutinin (PHA) or concanavalin A treatment of lymphocytes causes an increase in membrane permeability so that the leak rates of Na and K increase 1.5- to 2-fold. Active Na and K transport increase proportionately in response to the increased membrane permeability. We have examined the role of lymphocyte Na concentration in sustaining the increased Na and K transport observed after PHA...

Brain excitation increases neuronal Na(+) concentration by 2 major mechanisms: (i) Na(+) influx caused by glutamatergic synaptic activity; and (ii) action-potential-mediated depolarization by Na(+) influx followed by repolarizating K(+) efflux, increasing extracellular K(+) concentration. This review deals mainly with the latter and it concludes that clearance of extracellular K(+) is initially...

We report in this paper different modes of Na and K transport in human red cells, which can be inhibited by furosemide in the presence of ouabain. Experimental evidence is provided for inward and outward coupled transport of Na and K, Ki/Ko and Nai/Nao exchange, and uncoupled Na or K efflux. The outward cotransport of Na and K was defined as the furosemide-sensitive (FS) component of Na and K e...

Normal human red cells which have had their intracellular sodium (Na(c)) reduced have a diminished Na-K pump rate, but only if intracellular potassium (K(c)) is high. If most of the K(c) is replaced by tetramethylammonium or choline, both ouabain-sensitive Na efflux and K influx are significantly increased even with Na(c) below normal. Cells with reduced Na(c) and high K(c) have an unchanged Na...

screening methods that are effective in the early stage of growth will potentially provide the largest quantity of breeding material. although various screening methods under greenhouse have been proposed, potential effective approaches must be described a good correlation with results under field conditions. this study was aimed to assess the correlations between traits obtained from four salt...

cyprinus carpio is a stenohaline species but can tolerate some ranges of changes in environmental salinities, so histomorphological methods and na+-k+ atpase and aquaporin 3 immunohistochemistry were performed on common carp kidney as an osmoregulatory organ in experimental groups and control in order to investigate their possible roles during salinity challenge. five groups of fish (n=25) with...

introduction: ouabaine is a well-known atrioventricular (av) node depressant agent, but its effects on functional properties of the av node have not been cleared. the aim of the present study was to determine how ouabaine administration modifies the rate-dependent properties of the av node. methods: selective stimulation protocols were used to quantify independently electrophysiological propert...

a greenhouse research work was conducted to study the patterns of na+ and k+ distribution in root, stem and leaf during three growth stages of four iranian alfalfa ecotypes and to find correlation between these patterns and plant salt tolerance. treatments were replicated three times in a factorial experiment of a completely randomized block design. based on the threshold of salt tolerance in a...