Angiotensin converting enzyme inhibition does not prevent development of ACTH-induced hypertension in sheep.

The role of the renin-angiotensin system in the onset of ACTH-induced hypertension was examined in five conscious sheep. Captopril infusion alone (15 mg/kg per day) for 2 days produced a small fall in blood pressure. After 2 days of captopril ACTH was infused (20 micrograms/kg per day) for 3 days together with captopril. The blood pressure and electrolyte effects of ACTH administration were not modified by captopril pretreatment. These experiments establish that angiotensin II is not important in the onset of ACTH-induced hypertension in sheep.