Macrolide antibiotics such as erythromycin (EM) and azithromycin (AZM) are beneficial in the treatment of mucus hypersecretion in inflammatory pulmonary diseases. Several indirect and direct mechanisms of action have been proposed. This study investigates the direct effect of macrolides on secretory function of isolated submucosal mucous gland cells (SMGCs). We hypothesize that macrolides inhib...

PURPOSE To characterize the biophysical, pharmacologic, and functional properties of the Ca(2+)-activated Cl(-) current in retinal arteriolar myocytes. METHODS Whole-cell perforated patch-clamp recordings were made from myocytes within intact isolated arteriolar segments. Arteriolar tone was assessed using pressure myography. RESULTS Depolarizing of voltage steps to -40 mV and greater activ...

A hyposmotic challenge elicited contraction of isolated canine basilar arteries. The contractile response was nearly abolished by the removal of extracellular Ca(2+) and by the voltage-dependent Ca(2+) channel (VDCC) blocker nicardipine, but it was unaffected by thapsigargin, which depletes intracellular Ca(2+) stores. The contraction was also inhibited by Gd(3+) and ruthenium red, cation chann...

The enzyme carbonic anhydrase (CA), which is concentrated mainly in the osmoregulatory tissue of the gills, appears to be required for ion regulation but not for CO2 excretion. An injection of the CA inhibitor acetazolamide produced an inhibition of between 90 and 100 %, which took 6 h to be fully effective, and 48-96 h to wear off. During trie period of inhibition in Callinectes sapidus there ...

Pulmonary artery smooth muscle cell (PASMC) proliferation contributes to increased pulmonary vascular resistance and pulmonary hypertension. Because proliferation depends on membrane potential (V(m)) and because V(m) is, in part, determined by Cl(-) currents (I(Cl)), we examined the effects of I(Cl) inhibition with 4,4;-diisothiocyanatostilbene-2,2;-disulfonic acid (DIDS) on cultured rat PASMCs...

Cl(-) channels in the apical membrane of biliary epithelial cells (BECs) provide the driving force for ductular bile formation. Although a cystic fibrosis transmembrane conductance regulator has been identified in BECs and contributes to secretion via secretin binding basolateral receptors and increasing [cAMP](i), an alternate Cl(-) secretory pathway has been identified that is activated via n...

Abstract As an increasingly important aspect of water management, historical dry river-channels, ponds or lakes are operated for the storage reclaimed as a landscape with need reuse water. However, percolated may have adverse effect on groundwater quality. The aims this work to evaluate potential using various constituents characteristics tracers water, clarify hydrochemical process recharge, a...

The developmental rehearsal for the debut of hearing is marked by massive changes in the membrane properties of hair cells (HCs) and spiral ganglion neurons (SGNs). Whereas the underlying mechanisms for the developing HC transition to mature stage are understood in detail, the maturation of SGNs from hyperexcitable prehearing to quiescent posthearing neurons with broad dynamic range is unknown....

Cystic fibrosis (CF) is caused by defective cyclic AMP-dependent cystic fibrosis transmembrane conductance regulator Cl(-) channels. Thus, CF epithelia fail to transport Cl(-) and water. A postulated therapeutic avenue in CF is activation of alternative Ca(2+)-dependent Cl(-) channels. We hypothesized that stimulation of Ca(2+) entry from the extracellular space could trigger a sustained Ca(2+)...