Sodium channel protein epithelial 1 subunit alpha (SCNN1A)

The Sodium channel protein epithelial 1 subunit alpha (SCNN1A) is a fundamental component of the epithelial sodium channel (ENaC), which is responsible for the rate-limiting step of sodium reabsorption in the apical membrane of epithelial cells (UniProt P37088). It is predominantly expressed in the distal nephron of the kidney, the respiratory tract, and the colon, where it regulates fluid and electrolyte homeostasis (NCBI Gene: 6337). In the kidney, its activity is crucial for blood pressure regulation, and mutations leading to its overactivity result in Liddle syndrome, a hereditary form of hypertension (PubMed 30206103). In the lungs, ENaC mediates the absorption of liquid from the airway surface, a process that must be carefully balanced to ensure effective mucociliary clearance; its dysregulation is a hallmark of cystic fibrosis and chronic bronchitis (PubMed 25034177). Therapeutic targeting of SCNN1A involves inhibitors like amiloride and triamterene, which are used as potassium-sparing diuretics to treat hypertension and congestive heart failure (StatPearls NBK532954). Ongoing research also explores ENaC inhibitors for the treatment of cystic fibrosis to restore airway hydration and improve lung function (PubMed 27602072).

Other names

SCNN1ENaC-alphaAlpha-ENaCEpithelial sodium channel subunit alphaNonvoltage-gated sodium channel 1 subunit alphaAmiloride-sensitive sodium channel subunit alphaSCNEA

Direct physical blockade of the epithelial sodium channel (ENaC) pore, which prevents the entry of sodium ions from the extracellular or luminal space into the epithelial cell.