Response of renin, aldosterone and antidiuretic hormone to furosemide and furosemide-triamterene combination.

Plasma renin activity (PRA), antidiuretic hormone (ADH), urinary aldosterone excretion (U-Aldo) and electrolyte excretions were studied in a randomized study after furosemide (80 mg) (F), furosemide + triamterence (80 + 100 mg) (F + T), and after placebo were administered to seven healthy volunteers. F + T preparation showed a slower absorption of furosemide, a slower natriuresis and a slower excretion of potassium as compared to F-präparation. After application of the diuretics, PRA reached the maximal level in four hours, three times higher than the control level after F and four times higher after F + T. At 24 hrs after drug intake PRA did not differe from the control level. No significant difference could be found between F and F + T. U-Aldo of 24 hrs increased 1.9-fold after F and 2.2-fold after F + T, as compared with placebo. Between the individual natriuretic and hormonal responses no correlation could be found. After F + T, U-Aldo and U-K showed a positive correlation (P < 0.05). ADH did not change after diuretics from the pretreatment fasting level. The results show a fast but transient response of the renin-aldosterone system after furosemide and the furosemide-triamterene combination which could not be correlated with the natriuretic effects. The result differs from that found earlier with hydrochlorothiazide.