Epithelial sodium channels (ENaC) are uniformly distributed on motile cilia in the oviduct and the respiratory airways

  title={Epithelial sodium channels (ENaC) are uniformly distributed on motile cilia in the oviduct and the respiratory airways},
  author={Yehoshua Enuka and Israel Hanukoglu and Oded Edelheit and Hananya Vaknine and Aaron Hanukoglu},
  journal={Histochemistry and Cell Biology},
Epithelial sodium channels (ENaCs) are located on the apical surface of cells and funnel Na+ ions from the lumen into the cell. ENaC function also regulates extracellular fluid volume as water flows across membranes accompanying Na+ ions to maintain osmolarity. To examine the sites of expression and intracellular localization of ENaC, we generated polyclonal antibodies against the extracellular domain of human α-ENaC subunit that we expressed in E. coli. Three-dimensional (3D) confocal… 

Epithelial sodium channel (ENaC) in GtoPdb v.2021.2

The epithelial sodium channels (ENaC) are located on the apical membrane of epithelial cells in the kidney tubules, lung, respiratory tract, male and female reproductive tracts, sweat and salivary glands, placenta, colon, and some other organs and have a central role in regulating ECF volume and blood pressure.

Expression of epithelial sodium channel (ENaC) and CFTR in the human epidermis and epidermal appendages

The results reveal that ENaC is expressed strongly in all epidermal layers except stratum corneum, and also in the sebaceous glands, eccrine glands, arrector pili smooth muscle cells, and intra-dermal adipocytes, and co-localized with F-actin.

Progress in ciliary ion channel physiology

This review focuses on the composition of putative ion channels found in both types of cilia and in the periciliary membrane and discusses their proposed functions.

High‐resolution imaging of the actin cytoskeleton and epithelial sodium channel, CFTR, and aquaporin‐9 localization in the vas deferens

The localization of all three channels on the apical surface of the columnar epithelial cells provides clear evidence that these channels are involved concurrently in the regulation of fluid and electrolyte balance in the lumen of the vas deferens.

Cellular distribution and function of ion channels involved in transport processes in rat tracheal epithelium

The data demonstrate that, in rat tracheal epithelium, Cl− secretion and Na+ absorption are routed through different cell types, and that ANO1 channels form the molecular basis of Ca2+‐dependent Cl‐ secretion in this tissue.

Identification and classification of epithelial cells in nephron segments by actin cytoskeleton patterns

This study highlights the power of high‐resolution confocal microscopy for identifying specific cell types using the simple probe of F‐actin‐binding phalloidin to identify whole kidney sections by confocal microscopic imaging of fluorescent phalloids.

RAPID COMMUNICATION Site of Fluid Secretion in Small Airways

A mechanism in which the locations of secretory cells in the base of pleats and of absorptive cells in luminal folds physically help maintain a constant volume of ASL in small airways is proposed.

Site of Fluid Secretion in Small Airways.

A mechanism in which the locations of secretory cells in the base of pleats and of absorptive cells in luminal folds physically help maintain a constant volume of ASL in small airways is proposed.

Early Studies on the Surface Epithelium of Mammalian Airways.

  • J. Widdicombe
  • Biology
    American journal of physiology. Lung cellular and molecular physiology
  • 2019
The pace of research in most areas increased dramatically after the development of confluent, polarized cultures of airway epithelium in the early 1980s, and scores of molecules have been identified.



Early expression of beta- and gamma-subunits of epithelial sodium channel during human airway development.

Early expression of ENaC proteins in human fetal airways suggests that Na(+) absorption might begin significantly before birth, even if secretion is still dominant, as well as suggesting the distribution of its pore-forming alpha-, beta-, and gamma-subunits in the developing human lung.

Overview of structure and function of mammalian cilia.

Cilia are membrane-bounded, centriole-derived projections from the cell surface that contain a microtubule cytoskeleton, the ciliary axoneme, surrounded by a ciliary membrane. Axonemes in

Acute regulation of the epithelial sodium channel in airway epithelia by proteases and trafficking.

Findings demonstrate that Na(+) absorption in the airway is acutely modulated by the coordinated trafficking of channels to the luminal surface and by the proteolytic activation of ENaC in response to ASL volume expansion.

Motile Cilia of Human Airway Epithelia Are Chemosensory

Airway epithelia contain a cell-autonomous system in which motile cilia both sense noxious substances entering airways and initiate a defensive mechanical mechanism to eliminate the offending compound.

Soluble Mediators, Not Cilia, Determine Airway Surface Liquid Volume in Normal and Cystic Fibrosis Superficial Airway Epithelia

It is found that maneuvers that mimic deposition of excess ASL onto the proximal airways, which occurs during mucociliary clearance and after glandular secretion, acutely stimulated Na+ absorption, suggesting that volume regulation was sensitive to changes in concentrations of soluble mediators in the ASL rather than alterations in ciliary beating.

Identification of the roles of conserved charged residues in the extracellular domain of an epithelial sodium channel (ENaC) subunit by alanine mutagenesis.

It is established that while some conserved charged residues are part of the structure responsible for Na(+) self-inhibition, most are essential for transport to the oocyte cell surface.

Cell-specific expression of epithelial sodium channel alpha, beta, and gamma subunits in aldosterone-responsive epithelia from the rat: localization by in situ hybridization and immunocytochemistry

The data indicate that alpha, beta, and gamma subunit mRNAs and proteins are co-expressed in the distal nephron (excepting IMCD), a localization that correlates with the previously described physiological expression of amiloride-sensitive electrogenic sodium transport.

Early death due to defective neonatal lung liquid clearance in alpha-ENaC-deficient mice.

It is shown that ENaC plays a critical role in the adaptation of the newborn lung to air breathing and electrogenic Na+ transport was abolished in airway epithelia from alpha-ENaC(-/-) mice.

Regulation of the depth and composition of airway surface liquid

In airway diseases, the balance is shifted from water secretion to mucus secretion, and in bronchitis and asthma this is due mainly to conversion of gland serous to mucous cells.

Activation of the epithelial sodium channel (ENaC) by serine proteases.

Recent in vitro and in vivo experiments indicate that membrane-bound serine proteases are of critical importance in the activation of ENaC in different organs, such as the kidney, the lung, or the cochlea.