Inhibitory effect of cilazaprilat on norepinephrine release induced by renal nerve stimulation in anesthetized dogs

In pentobarbital-anesthetized dogs, the increase in the renal norepinephrine secretion rate elicited by renal nerve stimulation (1 Hz) during infusion of angiotensin I (15 ng/kg/min) was partially but significantly inhibited (by 21-37%) after dosing with cilazaprilat (0.1 mg/kg), an angiotensin converting enzyme inhibitor, accompanied by a decrease in the renal venous plasma norepinephrine concentration. These results may suggest that cilazaprilat exerts at least a part of its hypotensive effect through decreasing the facilitatory action of endogenous angiotensin II on adrenergic transmission.