Recent evidence suggests the expression of a Na(+)/Ca(2+) exchanger (NCX) in vascular endothelial cells. To elucidate the functional role of endothelial NCX, we studied Ca(2+) signaling and Ca(2+)-dependent activation of endothelial nitric-oxide synthase (eNOS) at normal, physiological Na(+) gradients and after loading of endothelial cells with Na(+) ions using the ionophore monensin. Monensin-...

The effects of insulin and ouabain on 22Na efflux and net Na loss were examined in frog sartorius muscles. After removal of ouabain, 22Na efflux which had been inhibited by ouabain remained at the inhibited level for more than 2 hr. In ouabain-free solution, insulin stimulated the Na efflux from ouabain-preincubated muscles. The stimulating effect of insulin on 22Na efflux was completely blocke...

Nanosecond scale molecular dynamics simulations have been performed on antiparallel Greek key type d(G7) quadruplex structures with different coordinated ions, namely Na+ and K+ ion, water and Na+ counter ions, using the AMBER force field and Particle Mesh Ewald technique for electrostatic interactions. Antiparallel structures are stable during the simulation, with root mean square deviation va...

In this study, quantitive characteristics and chemical composition of in roach (Rutilus rutilus caspicus) sperm were investigated. Sperm traits included sperm movement duration, percentage of motile spermatozoa, sperm density, spermatocrit and sperm volume. Some seminal plasma characteristics (sodium, potassium, calcium, magnesium and chloride) were investigated. In addition, some metabolites o...

Batrachotoxin (BTX)-activated Na+ channels from rabbit skeletal muscle were incorporated into planar lipid bilayers. These channels appear to open most of the time at voltages greater than -60 mV. Local anesthetics, including QX-314, bupivacaine, and cocaine when applied internally, induce different durations of channel closures and can be characterized as "fast" (mean closed duration less than...

Prokaryotic and eukaryotic Na(+)-driven transporters couple the movement of one or more Na(+) ions down their electrochemical gradient to the active transport of a variety of solutes. When more than one Na(+) is involved, Na(+)-binding data are usually analyzed using the Hill equation with a non-integer exponent n. The results of this analysis are an overall Kd-like constant equal to the concen...

In the present research synthesis of zeolites, merlinoite minerals of natural clinoptiloite mineral in the presence of alkaline mediums, was investigated. The analyzed variants are a result of a concentration of Na+ and K+ ions, temperature and time. Phase transition of clinoptiloite was conducted in the presence of an 8 molar potash solution (KOH) and a 4 molar soda solution (NaOH). Results in...

In this study, quantitive characteristics and chemical composition of in roach (Rutilus rutilus caspicus) sperm were investigated. Sperm traits included sperm movement duration, percentage of motile spermatozoa, sperm density, spermatocrit and sperm volume. Some seminal plasma characteristics (sodium, potassium, calcium, magnesium and chloride) were investigated. In addition, some metabolites o...

The Na+/K+ pump is a ubiquitous P-type ATPase that binds three cytoplasmic Na+ ions deep within its core where they are temporarily occluded before being released to the extracellular surface. The 3Na+/2K+ -exchange transport cycle is completed when two extracellular K+ ions bind and become temporarily occluded within the protein and subsequently released to the cytoplasm. Coupling of Na+ -ion ...

In the Na,K-ATPase the charge-translocating reaction steps were found to be binding of the third Na(+) ion to the cytoplasmic side and the release of all three Na(+) ions to the extracellular side as well as binding of the two K(+) ions on the extracellular side. The conformation transition E(1) --> E(2) was only of minor electrogenicity; all other reaction steps produced no significant charge ...