The amiloride-sensitive epithelial Na⁺ channel (ENaCs) family includes 4 members: ENaCα, β, γ and δ. The ENaC channel is located in the luminal (apical) plasma membrane of  several epithelial tissues such as kidney, lung, salivary glands and skin.  

The functional channel is believed to be a multimer including a α (or δ) and a β and γ subunits  with a likely stoichiometry of α2βγ.

ENaC channel enable entry of Na⁺ into the cell  along its electrochemical gradient and thus has a central role in the maintenance of  renal Na⁺ balance (and hence blood pressure) and liquid balance in the lung. Indeed, genetic mutations in the ENaC subunits causes Liddle’s syndrome (a form of hypertension) or pseudohypoaldosteronism type 1 (PHA) that is characterized by hypotension. 

The ENaC channel is voltage-independent and is constitutively active in epithelia although  it is modulated by several different mechanisms. One of the main mechanisms is the controlled internalization of the channel that is dependent  on the β or γ subunits. Indeed, mutations in the C-termini of these subunits reduce endocytosis  of the channel leading to the accumulation of ENaC in the cell membrane and causing a phenotype that is consistent with that of Liddle’s syndrome.