The cortical collecting duct (CCD) B cell possesses an apical anion exchanger dissimilar to AE1, AE2, and AE3. The purpose of these studies was to characterize this transporter more fully by examining its regulation by CO2 and HCO3. We measured intracellular pH (pHi) in single intercalated cells of in vitro microperfused CCD using the fluorescent, pH-sensitive dye, 2',7'-bis(2-carboxyethyl)-5(6...

Na-H exchanger NHE3 and Cl-anion exchanger CFEX (SLC26A6, PAT1) play principal roles in the reabsorption of Na and Cl in the proximal tubule of the mammalian kidney. The mechanisms by which NHE3 and CFEX are localized to and maintained in the brush border of the proximal tubule are largely unknown. To investigate the possible interaction of NHE3 and CFEX with the PDZ-domain-containing scaffoldi...

Slc26a2 is a ubiquitously expressed SO4 transporter with high expression levels in cartilage and several epithelia. Mutations in SLC26A2 are associated with diastrophic dysplasia. The mechanism by which Slc26a2 transports SO4 and the ion gradients that mediate SO4 uptake are poorly understood. We report here that Slc26a2 functions as a SO4/2OH, SO4/2Cl and SO4/OH/Cl exchanger, depending on the ...

A water-soluble and neutral polysaccharide was extracted from the current pseudobulbs of Oncidium "Gower Ramsey" during the early inflorescence stage (flower stalk less than 4 cm) by hot water, precipitated with ethanol, and purified with an anion exchanger. From the data of monosaccharide composition and linkage and anomeric configuration analyses, the polysaccharide was identified as a linear...

The nature of the intracellular pH-regulatory mechanism after imposition of an alkaline load was investigated in isolated human peripheral blood neutrophils. Cells were alkalinized by removal of a DMO prepulse. The major part of the recovery could be ascribed to a Cl-/HCO3- counter-transport system: specifically, a one-for-one exchange of external Cl- for internal HCO3-. This exchange mechanism...

Large volumes of saliva are generated by transepithelial Cl(-) movement during parasympathetic muscarinic receptor stimulation. To gain further insight into a major Cl(-) uptake mechanism involved in this process, we have characterized the anion exchanger (AE) activity in mouse serous parotid and mucous sublingual salivary gland acinar cells. The AE activity in acinar cells was Na(+) independen...

Layered double hydroxides (LDHs), also well-known as hydrotalcite-like layered clays, have been widely investigated in the fields of catalysts and catalyst support, anion exchanger, electrical and optical functional materials, flame retardants and nanoadditives. This feature article focuses on the progress in micro-/nanostructured LDHs in terms of morphology, and also on the preparations, appli...

BACKGROUND Some respiratory diseases may induce alveolar hypoxia thereby hypoxic pulmonary vasoconstriction (HPV). However, the mechanisms of this physiologic phenomenon are not fully understood. This study was the first to investigate the role of anion exchanger in sustained HPV. METHODS Experiments were performed in the isolated perfused rabbit lung. After preparation, the lungs were divide...

The rat liver sulfate/bicarbonate/oxalate exchanger (sat-1) transports sulfate across the canalicular membrane in exchange for either bicarbonate or oxalate. Sulfate/oxalate exchange has been detected in the proximal tubule of the kidney, where it is probably involved in the reabsorption of filtered sulfate and the secretion of oxalate and may contribute to oxalate-dependent chloride reabsorpti...

The pancreatic duct epithelium in the guinea-pig and many other species secretes HCO(3)(-) at concentrations approaching 150 mM. This cannot be explained by conventional models based upon HCO(3)(-) secretion via an anion exchanger at the luminal membrane because: 1) under these conditions, the Cl(-) and HCO(3)(-) concentration gradients would favour HCO(3)(-) reabsorption rather than secretion,...