ACTH-suppressive and vasodilator actions of adrenomedullin in conscious sheep

Abstract

Adrenomedullin (ADM) is a 52 amino-acid peptide which is a potent vasodilator in rats, and suppresses basal and CRF-induced ACTH release from cultured pituitary cells. The present study examines the hemodynamic and hormonal actions of human ADM (1-52) infusion in conscious, chronically instrumented sheep. Five sheep were infused intravenously (IV) or intracerebroventricularly (ICV) with ADM at 100 micrograms/h for 60 min, and mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume (SV), total peripheral conductance (TPC), coronary blood flow (CF), coronary conductance (CC), peak aortic flow (Fmax), and left ventricular dF/dt were monitored by a computer-based data c..