Pressor responsiveness in steroid-induced hypertension in man

Pressor responsiveness to angiotensin II (AII) and phenylephrine (PE) was examined before and after 5 days of ACTH (1 mg, i.m., daily) or hydrocortisone (200 mg, orally, daily) in six normotensive men. Pulse pressure was higher prior to PE than AII infusion, presumably due to feeding. Systolic blood pressure (SBP) was increased by both ACTH and hydrocortisone treatment, but more by ACTH. There were no significant changes in AII pressor responsiveness with either ACTH or hydrocortisone. ACTH increased pressor responsiveness to PE at 1.35 and 2 micrograms/kg per min, and hydrocortisone at 0.6-2 micrograms/kg per min, with falls in pulse rate at 0.3-0.9 micrograms/kg per min. Changes in pressor responsiveness do not explain ACTH hypertension.