Decreased blood pressure in response to an angiotensin II antagonist in Addison's disease

The synthetic angiotensin II antagonist, 1-sarcosine, 8-isoleucine angiotensin II was infused in two patients with untreated Addison's disease. Blood pressure decreased following infusion of this angiotensin II antagonist. Re-infusion of the antagonist after cortisol replacement therapy for one month caused a slight increase in blood pressure. Addison's disease is one of the conditions in which the renin-angiotensin system is involved in the maintenance of blood pressure.