NATRIURETIC EFFECTS OF DOPAMINE AGONIST DRUGS IN MODELS OF REDUCED RENAL MASS

In addition to recognized neurotransmitter properties in the central n ervous system, dopamine (DA) plays a role in the physiological activit y of the kidney through its hemodynamic and natriuretic effects. On th e basis of these data, some pharmacological interventions have focused their attention on the use of DA-related drugs to improve renal sodiu m handling. We summarize the data obtained from two studies using two DA agonist drugs, lisuride (LIS) and fenoldopam (FEN), in two situatio ns of reduced renal mass. During an intravenous sodium load performed on 10 uninephrectomized dogs, LIS induced a significant blockade of th e concomitant pressor response, estimated by lower blood pressure and norepinephrine levels. Under these same conditions, FEN significantly decreased blood pressure and elevated the natriuretic response. In a s econd study, when FEN was administered at nonhypotensive doses to chro nic renal failure patients, it evoked an enhancement of diuresis, natr iuresis, and creatinine clearance. These data seem to confirm the invo lvement of DA in the regulation of cardiovascular homeostasis and its role in renal sodium handling. Furthermore, these beneficial effects s upport the use of DA-related drugs in the field of hypertension.