Atrial natriuretic prohormone peptides 1-30, 31-67, and 79-98 vasodilate the aorta

Human prohormone atrial natriuretic Peptides 1-30, 31-67, and 79-98 caused vasodilation of porcine aortas which began in 30 seconds and was maximal at 10 minutes. These three Peptides were found to be equally potent to atrial natriuretic factor in their vasodilatory activity which was found with or without endothelium present. This vasodilation was associated with a 4 to 5 fold increase in cyclic GMP in the aorta secondary to activation of particulate Guanylate Cyclase [E.C. 4.6.12]. These data demonstrate that three N-terminal peptide segments of the atrial natriuretic factor prohormone cause vasodilation.