Intoxicated Na~+ channels. Focus on 'Ethanol stimulates epithelial sodium channels by elevating reactive oxygen species'

摘要

sodium absorption across epithelia in the kidney is critical for the maintenance of extracellular volume and for the regulation of blood pressure. Excessive Na~+ absorption is responsible for the majority of inherited forms of hypertension, whereas inadequate Na~+ absorption causes Na~+ wasting and hypotension (10). In the lung, Na~+ absorption maintains the quantity and composition of airway surface liquid, which is critical for gas exchange and host defense, In the kidney and lung, the epithelial Na~+ channel, ENaC, plays a key role in Na~+ absorption (reviewed in Refs. 15, 17).ENaC is located at the apical membrane, where it conducts Na~+ from the extracellular environment into the cell. Coupled with Na~+ exit at the basolat-eral membrane via the Na~+-K~+-ATPase, ENaC functions as a pathway for Na~+ absorption.