In ischemic preconditioning, a sublethal ischemic insult protects neurons from subsequent ischemia. In organotypic hippocampal slice cultures a sublethal 5-minute hypoxia-hypoglycemia treatment prevented neuronal loss after a 10-minute experimental ischemic (EI) treatment of hypoxia-hypoglycemia. Whereas preconditioning protected against EI given 24 h later, it did not protect when EI was given...

Late in gestation, the developing air space epithelium switches from chloride and fluid secretion to sodium and fluid absorption. Absorption requires Na-K-ATPase acting in combination with apical sodium entry mechanisms. Hypothyroidism inhibits perinatal fluid resorption, and thyroid hormone [triiodothyronine (T3)] stimulates adult alveolar epithelial cell (AEC) Na-K-ATPase. This study explored...

Through their ion-pumping and non-ion-pumping functions, Na(+)-K(+)-ATPase protein complexes at the plasma membrane are critical to intracellular homeostasis and to the physiological and pharmacological actions of cardiotonic steroids. Alteration of the abundance of Na(+)-K(+)-ATPase units at the cell surface is one of the mechanisms for Na(+)-K(+)-ATPase regulation in health and diseases that ...

The alveolar epithelium is composed of alveolar type 1 (AT1) and alveolar type 2 (AT2) cells, which represent approximately 95% and approximately 5% of the alveolar surface area, respectively. Lung liquid clearance is driven by the osmotic gradient generated by the Na,K-ATPase. AT2 cells have been shown to express the alpha1 Na,K-ATPase. We postulated that AT1 cells, because of their larger sur...

Erythrocytes are useful in evaluating K+ transport pathways involved in internal K+ balance. Several forms of H+,K+-ATPase have been described in nephron segments active in K+ transport. Furthermore, the activity of a ouabain-insensitive isoform of H+,K+-ATPase expressed in collecting duct cells may be modulated by acid-base status. Various assays were performed to determine if a ouabain-insens...

Nitric oxide (NO) plays an important role in the control of numerous vascular functions including basal Na+-K+-ATPase activity in arterial tissue. Hyperglycemia inhibits Na+-K+-ATPase activity in rabbit aorta, in part, through diminished bioactivity of NO. The precise mechanism(s) for such observations, however, are not yet clear. The purpose of this study was to examine the role of superoxide ...

Na,K-ATPase is an essential gene maintaining electrochemical gradients across the plasma membrane. Although previous studies have intensively focused on the role of Na,K-ATPase in regulating cardiac function in the adults, little is known about the requirement for Na,K-ATPase during embryonic heart development. Here, we report the identification of a zebrafish mutant, heart and mind, which exhi...

Na,K-ATPase is a key enzyme that regulates a variety of transport functions in epithelial cells. In this study, we demonstrate a role for Na,K-ATPase in the formation of tight junctions, desmosomes, and epithelial polarity with the use of the calcium switch model in Madin-Darby canine kidney cells. Inhibition of Na,K-ATPase either by ouabain or potassium depletion prevented the formation of tig...

The successful migration of euryhaline teleost fish from freshwater to seawater requires the upregulation of gill Na+-K+-ATPase, an ion transport enzyme located in the basolateral membrane (BLM) of gill chloride cells. Following 39 days of seawater exposure, Arctic char had similar plasma sodium and chloride levels as individuals maintained in freshwater, indicating they had successfully acclim...

Deactivation of glutamatergic signaling in the brain is mediated by glutamate uptake into glia and neurons by glutamate transporters. Glutamate transporters are sodium-dependent proteins that putatively rely indirectly on Na,K-ATPases to generate ion gradients that drive transmitter uptake. Based on anatomical colocalization, mutual sodium dependency, and the inhibitory effects of the Na,K-ATPa...