Electroneutral cation-chloride cotransporters are widely expressed and perform a variety of physiological roles. A novel gene family of five members, encompassing a Na+-Cl- transporter, two Na+-K+-2Cl- transporters and two K+-Cl- cotransporters, encodes these membrane proteins; homologous genes have also been identified in a prokaryote and a number of lower eukaryotes. The cotransporter protein...

A role of nitric oxide (NO) in the regulation of sodium transporters and water channels in the salivary gland was investigated. Male Sprague-Dawley rats were treated with N(G) -nitro-L-arginine methyl ester (L-NAME, 100 mg/L drinking water) for 1 week. The control group was supplied with normal tap water. The expression of Na(+),K(+)-ATPase, type 2 Na(+)/K(+)/2Cl(-) cotransporter (NKCC2), type ...

Na+K+2Cl- co-transporters (NKCCs) effect the electroneutral movement of Na+-K+ and 2Cl- ions across the plasma membrane of vertebrate cells. There are two known NKCC isoforms, NKCC1 (Slc12a2) and NKCC2 (Slc12a1). NKCC1 is a ubiquitously expressed transporter involved in cell volume regulation, Cl- homeostasis and epithelial salt secretion, whereas NKCC2 is abundantly expressed in kidney epithel...

Aldosterone increases cation transport and contractility of vascular smooth muscle, but the specific transporter involved and how it is linked to smooth muscle tone is unknown. Because the Na-K-2Cl cotransporter (NKCC1) contributes to vascular smooth muscle contraction and is regulated by vasoactive compounds, we sought to determine whether this transporter is a target of aldosterone in rat aor...

Tritrichomonas foetus was shown to undergo a regulatory volume increase (RVI) when it was subjected to hyperosmotic challenge, but there was no regulatory volume decrease after hypoosmotic challenge, as determined by using both light-scattering methods and measurement of intracellular water space to monitor cell volume. An investigation of T. foetus intracellular amino acids revealed a pool siz...

Two isoforms of the cation-Cl(-) cotransporter family are expressed in neurons and modulate neurotransmission. NKCC1, a Na(+)-K(+)-2Cl(-) cotransporter, by raising internal Cl(-), is responsible for excitatory GABAergic activity in immature brain and in adult sensory neurons. KCC2, a neuronal-specific isoform of the K(+)-Cl(-) cotransporter, by lowering internal Cl(-), is critical for inhibitor...

The balance of K+, Na+, and Cl– fluxes across the cell membrane with the Na+/K+ pump, ion channels, and Na+K+2Cl– (NKCC) and Na+–Cl– (NC) cotransport was calculated to determine the mech anism of cell shrinkage in apoptosis. It is shown that all unidirectional K+, Na+, and Cl– fluxes; the ion chan nel permeability; and the membrane potential can be found using the principle of the flux balance ...

[Formula: see text]/NH3fluxes were used to probe apical Na-K-2Cl transport activity of macula densa (MD) cells from rabbit kidney. In the presence of 25 mM NaCl and 5 mM Ba2+, addition of 20 mM[Formula: see text] to the lumen produced a profound intracellular acidification, and ∼80% of the initial acidification rate was bumetanide sensitive. The[Formula: see text]-induced acidification rate was...