Urinary prostasin in humans: relationships among prostasin, aldosterone and epithelial sodium channel activity.

Prostasin, a membrane-bound serine protease, is known to increase the activity of the epithelial sodium channel (ENaC). Gene expression of prostasin was shown to be regulated by aldosterone, which increases the rate of sodium reabsorption through ENaC. To clarify the physiological relationships among prostasin, aldosterone and ENaC, we developed a specific radioimmunoassay (RIA) for human prostasin.