Clonidine s.c. (0.01-0.3 mg/kg), in unanesthetized rats, caused an initial rise (+20 mm Hg), followed by a continuous fall of BP and a dose-dependent natriuresis and diuresis for up to 2 h. Glomerular filtration rate (GFR) (CIn) increased during the first 20 min, while effective renal plasma flow