Epithelial Na(+) channels are regulated by flow.

Flow cytometry analysis reveals a decrease in intracellular sodium during sperm capacitation.

Mammalian sperm require time in the female tract in order to be able to fertilize an egg. The physiological changes that render the sperm able to fertilize are known as capacitation. Capacitation is associated with an increase in intracellular pH, an increase in intracellular calcium and phosphorylation of different proteins. This process is also accompanied by the hyperpolarization of the sper...

Nasal potential difference to detect Na+ channel dysfunction in acute lung injury.

Pulmonary fluid clearance is regulated by the active transport of Na(+) and Cl(-) through respiratory epithelial ion channels. Ion channel dysfunction contributes to the pathogenesis of various pulmonary fluid disorders including high-altitude pulmonary edema (HAPE) and neonatal respiratory distress syndrome (RDS). Nasal potential difference (NPD) measurement allows an in vivo investigation of ...

Ionic blockage of the light-regulated sodium channels in isolated rod outer segments

We have investigated, with osmotic techniques, the light-regulated Na+ channels in rod outer segments (ROS) and ROS fragments freshly isolated from the frog retina. Values of Na+ permeability (PNa) similar to those observed electrophysiologically in the retina were observed using the osmotic technique (continuous flow) described by Korenbrot and Cone. In the other osmotic techniques that we exp...

Glucocorticoid-stimulated Na transport in human lung epithelia is associated with regulated ENaC and sgk1 expression. H441 CELLS, A BRONCHIOLAR EPITHELIAL CELL WITH GLUCOCORTICOID-REGULATED NA TRANSPORT, EXPRESS CLASSIC ENAC CHANNELS

Hypoxia downregulates expression and activity of epithelial sodium channels in rat alveolar epithelial cells.

Decrease in alveolar oxygen tension may induce acute lung injury with pulmonary edema. We investigated whether, in alveolar epithelial cells, expression and activity of epithelial sodium (Na) channels and Na,K-adenosine triphosphatase, the major components of transepithelial Na transport, were regulated by hypoxia. Exposure of cultured rat alveolar cells to 3% and 0% O2 for 18 h reduced Na chan...