Amiloride at millimolar concentrations caused marked changes in the growth-dependent intracellular balance of Na+ and K+ in Streptococcus faecalis. These results, whether specific to transport processes or resulting from indirect yet unknown mechanisms, constitute the first evidence of an effect of amiloride on bacterial electrolytes.

Nebulized amiloride has been proposed as therapy in cystic fibrosis to block Na+ hyperabsorption in airway epithelium and prevent dehydration of secretions. Patients with cystic fibrosis often have reactive airways. Bovine and canine trachea relax to amiloride in vitro, suggesting another benefit as a bronchodilator, whereas guinea pig trachea, a useful model of human airways, does not. We hypo...

Hypoxia has been reported to inhibit activity and expression of ion transporters of alveolar epithelial cells. This study extended those observations by investigating the mechanisms underlying inhibition of active Na transport across primary cultured adult rat alveolar epithelial cell monolayers grown on polycarbonate filters. Cell monolayers were exposed to normoxia and hypoxia (1.5% and 5% O(...

BACKGROUND Amiloride derivatives, commonly used for their diuretic and antihypertensive properties, can also cause a sustained but reversible decrease of intracellular pH (pHi). Using dimethyl amiloride (DMA) on normal rodent pancreatic islets, we previously demonstrated the critical influence of islet pHi on insulin secretion. Nutrient-stimulated insulin secretion (NSIS) requires a specific pH...

STONER, L. C., M. B. BURG, AND J. ORLOFF. Ion transport in cortical collecting tubule; effect of amiloride. Am. J. Physiol. 227(2) : 453-459. 1974.-T b 1 u u es were dissected from rabbit kidneys and perfused in vitro. In cortical collecting tubules the transepithelial electrical potential difference (PD) was 35 mV (lumen negative). There was net active sodium reabsorption from the lumen and ne...

When toad urinary bladder or frog skin epithelia are treated with amiloride, short-circuit current (Isc), which represents the net active transepithelial Na+ transport rate from the apical to basolateral surface, decreases rapidly (2-5 s) to approximately 15-20% of control values and then slowly, over several minutes, continues falling toward zero. The contribution of this second phase of the d...

The epithelial sodium channel (ENaC) is important for the long-term control of Na(+) homeostasis and blood pressure. Our previous studies demonstrated that Copper Metabolism Murr1 Domain-containing protein 1 (COMMD1; previously known as Murr1), a protein involved in copper metabolism, inhibited amiloride-sensitive current in Xenopus laevis oocytes expressing ENaC (J Biol Chem 279: 5429, 2004). ...

Furosemide administration stimulates distal acidification. This has been attributed to the increased lumen-negative voltage in the distal nephron, but the aspect of regulatory mechanisms of H(+)-ATPase has not been clear. The purpose of this study is to investigate whether chronic administration of diuretics alters the expression of H(+)-ATPase and whether electrogenic Na(+) reabsorption is inv...

KIRSCHNER, LEONARD B., LEWIS GREEN~ALD, AND THEODORE H. KERSTETTER. Effect of amiloride on sodium transport across body surfaces of freshwater animals. Am. J. Physiol. 224(4): 832-837. 1973.-Amiloride, added to an external bathing solution at a concentration of 1 X 10m4 M, inhibited sodium influx in intact trout (79 %), frogs (460/,), and crayfish (90 yO). It had no effect on efflux across the ...