Natriuretic hormone.

The factors that control sodium excretion have been the subject of considerable work in recent years. The natriuresis that follows expansion of the extracellular fluid volume is mediated to a large extent by inhibition of tubular sodium reabsorption. Of the several mechanisms proposed to explain this inhibition, considerable interest has followed the suggestion that a humoral substance is released into the blood stream in response to volume expansion. The present article reviews the evidence for and against the existence of such a humoral substance (natriuretic hormone). It also discusses its proposed chemical nature and its possible site of origin in the organism as well as its mode of action.