Tubular sites and mechanisms of diuretic action.

. In its strictest sense diuresis is a term that implies increase in urine flow, and diuretics those agents that effect this change. In the present review, however, diuretics will be defined as clinically useful pharmacological agents which induce a net loss of water and sodium in the urine. In bringing about this change a number of renal and extrarenal systems and functions may be altered. Within the kidney itself a number of complex vascular, humoral, and biochemical events may ensue. Although virtually all diuretics in common use alter the GFR their actions are generally independent of it. Inhibition by diuretics of tubular reabsorption of sodium and water, therefore, may be inferred. This review pertains to the current concepts of the tubular actions of diuretics and the evidence on which they rest.