Effect of 9-α-Fluorohydrocortisone on Forearm Vascular Responses to Norepinephrine

Abstract

Vascular responses to norepinephrine were studied in normal subjects during three sessions. The first session took place before steroid treatment. The second session took place 1 week after daily oral administration of 9-α-fluorohydrocortisone. The third session was conducted 3 weeks after stopping treatment. Forearm blood flow decreased and forearm vascular resistance increased more during norepinephrine infusions in the session immediately after the administration of 9-α-fluorohydrocortisone than in either control session. Increases in resistance against the same levels of blood pressure in the session after steroid treatment indicate that the responsiveness of vascular smooth muscle to norepinephrine was augmented after 1 week of treatment with 9-α-fluorohydrocortisone. The data indicate that blood flow to the forearm during norepinephrine infusion is not enhanced by administration of fluorohydrocortisone.