Sodium channel epithelial 1 subunit delta (SCNN1D)

Sodium channel epithelial 1 subunit delta (SCNN1D) encodes the delta subunit of the epithelial sodium channel (ENaC), a heterotrimeric non-voltage-gated ion channel that regulates sodium ion transport across epithelial cell membranes[1][2][5]. ENaC channels, composed of various combinations of α, β, γ, and δ subunits, are primarily responsible for sodium absorption in tissues such as the brain, pancreas, testis, ovary, lung, and vascular endothelium[1][2][4][5]. Unlike voltage-gated sodium channels involved in neuronal action potentials, ENaC is constitutively active and plays a central role in maintaining extracellular fluid osmolarity, blood pressure, and overall sodium homeostasis[1][2][4][5]. The delta subunit is less prevalent in classic sodium-transporting tissues (kidney, colon), instead showing distinctive expression in the central nervous system and select extrarenal sites[1][2][4]; its modulation affects ion selectivity, conductance, and sensitivity to amiloride[2][4][5]. The gene, located on chromosome 1p36, produces channels with specialized biophysical and regulatory characteristics relevant to disease pathophysiology, including hypertension, inflammatory responses, and pulmonary diseases. Although rare variants have been linked to blood pressure regulation and kidney function, delta subunit mutations are not known to cause specific Mendelian syndromes[4]. Amiloride and related ENaC inhibitors act on ENaC, including delta-containing channels, making this subunit a drug target for disorders of sodium retention, hypertension, and edema[1][2][4][5].

Other names

Epithelial sodium channel subunit deltaDelta-ENaCENaC deltadNaChAmiloride-sensitive sodium channel subunit deltaDelta-NaCHNonvoltage-gated sodium channel 1 subunit deltaENaCdSCNEDDNACH

Drugs such as amiloride block ENaC, reducing sodium reabsorption and affecting fluid balance. Inhibition of ENaC leads to decreased sodium transport across epithelia, with downstream effects on blood pressure and edema