The electrical signals of neurons are fundamentally dependent on voltage-gated sodium channels (VGSCs), which are responsible for the rising phase of the action potential. An array of naturally occurring and synthetic neurotoxins have been identified that modify the gating properties of VGSCs. Using murine neocortical neurons in primary culture, we have compared the ability of VGSC gating modif...

Sodium transport of erythrocytes from normotensive and essential hypertensive subjects was evaluated by determining ouabain-sensitive and ouabain-insensitive sodium efflux rates, Na+-Li+ countertransport rates, Li+-K+ cotransport rate constants (lithium replacing sodium), intracellular sodium concentrations, and the number of Na+,K+-adenosine triphosphatase (ATPase) sites per erythrocyte. Subje...

Sodium selenite (1 mg/kg body weight, ip) for 10 consecutive days treatment showed marked increase in intra-erythrocytes K+ and plasma Na+ level while slight increase in Na+ K+ ATPase level. No mortality was observed at this dose of sodium selenite. However, sodium selenite pretreatment partially restored the Na+ K+ ATPase and intra-erythorcytes and plasma sodium level, while completely restore...

The total cross sections for Inelastic collisions between excited sodium and noble gas atoms in their ground states, leading to 2 2 3 P^y2 — — 3 ^3/2 excitation transfer in sodium, have been determined in a series of sensitized fluorescence experiments with pure sodium vapour and its mixtures with noble gases. In the experiments with pure sodium, the sodium vapour pressure was varied over the r...

Na/K-ATPase signaling has been implicated in different physiological and pathophysiological conditions. Accumulating evidence indicates that oxidative stress not only regulates the Na/K-ATPase enzymatic activity, but also regulates its signaling and other functions. While cardiotonic steroids (CTS)-induced increase in reactive oxygen species (ROS) generation is an intermediate step in CTS-media...

OBJECTIVES To implement different sodium (²³Na)-magnetic resonance imaging (MRI) contrasts at 3 Tesla and to evaluate if a weighting toward intracellular sodium can be achieved, using 2 rare muscular channelopathies as model diseases. MATERIALS AND METHODS Both lower legs of 6 patients with hypokalemic periodic paralysis (HypoPP), 5 patients with paramyotonia congenita (PC), and 5 healthy vol...

Dehydration causes an increase in the sodium (Na) concentration and osmolarity of body fluids. For Na homeostasis of the body, control of Na and water intake and excretion are of prime importance. Although the circumventricular organs (CVOs) were suggested to be involved in body-fluid homeostasis, the system for sensing Na levels within the brain, which is responsible for the control of Na- and...

macrobrachium rosenbergii lifecycle is unique so that the adults thrive in freshwater and larval development requires brackish water environments near to estuaries as close as possible to larval body isosmotic for minimum na/k-atpase activity and maximum atp storage. osmoregulation system at early larval stages is not formed and larval osmoregulation is mainly attributed to na/k-atpase activity...

Verapamil (10(-6) M) significantly reduced a development of the membrane depolarization and the contracture which were induced by Na removal. The fully developed depolarization, after exposure to Na-free solution, was reduced greatly by verapamil, excess Ca (15 mM) or sodium nitroprusside (10(-6) M), but some depolarization still remained. This remaining depolarization was completely blocked by...

Various parameters of erythrocyte membrane sodium transport were measured in patients with untreated essential hypertension, in the normotensive offspring of parents with hypertension, and in patients whose hypertension had been controlled by medication. Net sodium efflux, measured by an isotopic tracer technique, was 2.12 +/- 0.17 mM Na+/1 of red blood cells (RBCs)/hr in patients with untreate...