[A study on the pathophysiology and diagnosis of adrenocortical insufficiency using angiotensin II blocker (author's...

Angiotensin II analogue (AIIA), 1-sarcosine, 8-isoleucine angiotensin II (Sar1, Ile8-AII), was given in a graded dose to patients with adrenal hypofunction of various etiologies, and the blood pressure response to AIIA was observed to investigate the role of the renin-angiotensin system for the maintenance of blood pressure in the state of adrenal insufficiency. An agonistic pressor response to AIIA was observed in the control subjects without adrenal hypofunction. In contrast with this, patients with Addison's disease showed a blood pressure fall to AIIA. When the test was repeated on the same patients after hydrocortisone replacement, these patients showed a neutral or pressor response. Three patients with adrenalectomy and hydrocortisone replacement showed a pressor response to AIIA in a supine position. When these patients were tilted, fall in blood pressure to AIIA was observed in two of them who had been on a regular diet, whereas one patient who had been on a high sodium diet showed no fall in blood pressure with this procedure. We concluded that the renin-angiotensin system plays an important role in the maintenance of normal or subnormal blood pressure in Addison's disease and in the postural change of adrenalectomized patients on hydrocortisone and regular salt intake. The response of blood pressure to AIIA may be a clue for the diagnosis of Addison's disease and the evaluation of the adequacy of replacement therapy with regard to these patients.