The steady-state transport kinetics of the interaction between external sodium and the diuretic drug, amiloride, was studied in isolated anuran skin epithelia. We also investigated the effect of calcium on the amiloride-induced inhibition of short-circuit current (Isc) in these epithelial preparations. The major conclusions of this study are: (a) amiloride is a noncompetitive inhibitor of Na en...

Epithelial sodium channel (ENaC) blockers have been proposed as a therapy to restore mucus clearance (MC) in cystic fibrosis (CF) airways. The therapeutic effects of the first generation ENaC blocker, amiloride, in CF patients, however, were minimal. Because the failure of amiloride reflected both its low potency and short duration of action on airway surfaces, we investigated whether the incre...

Amiloride, a sodium channel blocker, is known to suppress NaCl responses of the chorda tympani (CT) nerve in various mammalian species. In mice, the NaCl suppressing effect of amiloride is reported to differ among strains. In C57BL mice, amiloride inhibits NaCl responses to about 50% of control, whereas no such clear suppression was evident in prior studies with 129 mice. However, evidence from...

We examined the effect of amiloride on Na+-H+ exchange in rabbit renal cortical microvillus membrane vesicles. Amiloride inhibited both the uphill Na+ accumulation induced by imposition of a transmembrane Hin+ greater than Hout+ gradient and the uphill H+ efflux induced by imposition of a Naout+ greater than Nain+ gradient. The inhibitory effect of amiloride on Na+ influx was rapidly reversible...

Amiloride, a potassium sparing diuretic, is well known to interact with many ion transport systems and modulate the activity of several membrane receptors. However, relatively little information is available as to how amiloride affects membrane receptors of neurons in the brain areas. In the present study, we investigated the effects of amiloride on glycine-induced currents (I(Gly)) in cultured...

Diamine oxidase (histaminase), an enzyme that oxidatively deaminates putrescine and histamine, was purified from human placenta and from pig kidney. Both NH2-terminal sequences are highly homologous to the human kidney amiloride-binding protein, previously thought to be a component of the amiloride-sensitive Na+ channel. Monoclonal antibodies raised against the pig kidney amiloride-binding prot...

This study was undertaken to investigate the effects of the potassium-retaining diuretic, amiloride, on the potassium balance and on the alkalosis which occurs in patients after open-heart surgery. Patients who had had valve replacement operations were divided randomly into two groups, one of which received Io mg amiloride daily in the postoperative period. Patients who were given amiloride nee...

BACKGROUND Amiloride has been reported to produce a wide variety of actions, thereby affecting several ionic channels and a multitude of receptors and enzymes. Intrathecal α2-adrenergic receptor agonists produce pronounced analgesia, and amiloride modulates α2-adrenergic receptor agonist binding and function, acting via the allosteric site on the α2A-adrenergic receptor. OBJECTIVES To investi...

The urokinase receptor (uPAR) and its soluble form play a key role in the pathogenesis of focal segmental glomerulosclerosis (FSGS). The modification of uPAR pathological actions on podocytes will become an important task for the development of improved nephroprotective therapeutics. Here we show that podocyte uPAR expression can be reduced using amiloride. Amiloride has a significant role in t...