Abstract
There is evidence to suggest that the regulation of systemic blood pressure by the kidney is, in part, an expression of a renal antihypertensive endocrine function, that sodium secretion by the kidney may be related to the presence of a natriuretic "hormone," and that intrarenal prostaglandins may be involved in the mechanisms of both of these renal functions. Prostaglandin (PGA and PGE) compounds, when administered to hypertensive man, decrease blood pressure, increase renal blood flow, and promote a water and sodium diuresis. Circulating plasma PGA concentrations have been found to be lower in hypertensive man than in the normotensive state. Mechanisms are proposed by which PGA or PGE may function as an intrarenal hormone and by which PGA may function as a circulating hormone to regulate blood pressure.