Contribution of renal nerves to the natriuretic and diuretic effect of alpha-2 adrenergic receptor activation

To determine the contribution of renal nerves to natnuresis produced by selective alpha-2 adrenergic receptor activation in volume-loaded, lnactin-anesthetized rats, responses to B-HT 933 (20 g/kg/min, i.v.) were compared in the chronically de-nervated kidney with responses in the contralateral innervated kidney. Plasma vasopressin concentration was maintained at high physiological levels by constant infusion of arginine vaso-pressin (1 70 pg/kg/mm, i.v.). Control rats received arginine vas-opressin and saline only. Arterial pressure and heart rate were decreased significantly by B-HT 933 (1 2 mm Hg and 80 beats/ mm, respectively). Glomerular filtration rate was not altered in innervated or denervated kidneys, whereas renal blood flow was decreased slightly, but significantly, in denervated but not inner-vated kidneys. B-HT 933 increased urine flow and total an