Hypoxia-induced inhibition of whole cell membrane currents and ion transport of A549 cells.

In excitable cells, hypoxia inhibits K channels, causes membrane depolarization, and initiates complex adaptive mechanisms. It is unclear whether K channels of alveolar epithelial cells reveal a similar response to hypoxia. A549 cells were exposed to hypoxia during whole cell patch-clamp measurements.

Hypoxia-effects on Ca(i)-signaling and ion transport activity of lung alveolar epithelial cells.

In excitatory cells specific responses upon changes in PO(2) are mediated by changes in intracellular Ca (Ca(i)). We wanted to know whether ion transport of lung alveolar epithelial cells is regulated by Ca(i) and whether Ca(i) and Ca(i) -signaling are affected by hypoxia in a way that might explain hypoxic transport inhibition (Mairbäurl et al. AJP 273: L797, 1997).

Hypoxia decreases proteins involved in epithelial electrolyte transport in A549 cells and rat lung.

Fluid reabsorption from alveolar space is driven by active Na reabsorption via epithelial Na channels (ENaCs) and Na-K-ATPase. Both are inhibited by hypoxia. Here we tested whether hypoxia decreases Na transport by decreasing the number of copies of transporters in alveolar epithelial cells and in lungs of hypoxic rats.

Possible role of ROS as mediators of hypoxia-induced ion transport inhibition of alveolar epithelial cells.

In oxygen-sensitive excitable cells, responses to hypoxia are initiated by membrane depolarization due to closing of the K channels that is thought to be mediated by a decrease in reactive oxygen species (ROS). Because the mechanisms of hypoxic inhibition of ion transport of alveolar epithelial cells (Planes C, Friedlander G, Loiseau A, Amiel C, and Clerici C. Am J Physiol Lung Cell Mol Physiol 271: L70-L78, 1996; Mairbäurl H, Wodopia R, Eckes S, Schulz S, and Bärtsch P.

Induction of tubular peroxisomes by UV irradiation and reactive oxygen species in HepG2 cells.

Peroxisomes in the human hepatoblastoma cell line HepG2 exhibit a high degree of plasticity. Whereas in confluent cultures they appear as small (0.1-0.