To the Editor.—
After de Bold et al1 reported a rapid and a potent natriuretic response induced by intravenous injection of atrial myocardial extract in rats, the capacity of atrial natriuretic peptide (ANP) as a hormone to induce natriuresis has been confirmed by the research of many workers. It has been reported that the secretion of this hormone depends on volume balance.2 However, it has yet to be determined whether this volume dependency results from an increased extracellular fluid (ECF) volume per se or is associated with a high intake of salt.3 In this study, an examination was carried out on dependency of the plasma level of human ANP on volume and sodium balance in a patient with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) possibly related to both these factors.
Report of a Case.—
A 74-year-old man was admitted to our hospital because of