ENaC mutation is associated with

ENac (Epithelial sodium channel)*ENac is a sodium transpo channel that is produced in the apical surface of all exocrine epithelial cells (All tracts and ducts)*The channel absorbs sodium from the luminal secretions and sent it back to the circulation thus maintaining the sodium level in blood and hence normal blood pressure.*Mutation of this ENaC channel will cause loss of sodium through luminal secretions and causes hyponatremia and hypovolemia. This in turn stimulates Renin angiotensin system causing hypeension through aldosterone. This condition is called "Liddle syndrome"*ENac is downregulated by CFTR gene in normal individuals. In cystic fibrosis, loss of CFTR causes increased expression of ENaC in all the tracts and ducts except sweat ducts. In sweat ducts, the function of ENaC channel is impaired causing "salty sweat" ( Ref: Robbins 8/e p493)