The epithelial sodium channel ENaC consists of three subunits encoded by Scnn1a, Scnn1b, and Scnn1g and increased sodium absorption through this channel is hypothesized to lead to mucus dehydration and accumulation in cystic fibrosis (CF) patients.
Loss-of-function mutations of the MR are responsible for renal pseudohypoaldosteronism type 1 (PHA1), a rare disease of mineralocorticoid resistance presenting in the newborn with weight loss, failure to thrive, vomiting and dehydration, associated with hyperkalemia and metabolic acidosis, despite extremely elevated levels of plasma renin and aldosterone.
Loss-of-function mutations in two key components of the aldosterone response, the mineralocorticoid receptor and the epithelial sodium channel ENaC, lead to type 1 pseudohypoaldosteronism (PHA1), a rare genetic disease of aldosterone resistance characterized by salt wasting, dehydration, failure to thrive, hyperkalemia and metabolic acidosis.
CLD is an autosomal recessive disorder of intestinal electrolyte absorption caused by mutations in the solute carrier family 26, member 3 (SLC26A3) gene, and continuous production of watery diarrhea induces dehydration, metabolic alkalosis and many kinds of electrolyte disturbances in CLD patients.
The NKCC2 transporter decrease in the thick ascending loop of Henle secondary to the ageing could explain the reduced sodium reabsorption of this segment in the healthy elderly and its potential clinical consequences of dehydration and serum sodium abnormalities.
Newborn spink5(R820X/R820X) mice develop a lethal, severe ichthyosis with a loss of skin barrier function and dehydration, resulting in death within a few hours of birth, similar to that observed in patients with severe Netherton syndrome.
Cystic fibrosis (CF) is a disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) that in the airways result in reduced Cl<sup>-</sup> secretion and increased Na<sup>+</sup> absorption, airway surface liquid (ASL) dehydration, decreased mucociliary clearance, infection and inflammation leading to lung injury.