Vascular effects of natriuretic peptides in healthy men.

Background: Most effects of atrial (ANP) and B-type natriuretic peptide (BNP) result from stimulation of the guanylyl-cyclase type A receptor. Chronic elevation causes hyporesponsiveness to ANP, whereas BNP effects tend to be preserved, implying an additional pathway of action. We, therefore, investigated the hemodynamic effects of co-infusion of ANP, BNP, and, as a positive control acting on type B receptor, C-type natriuretic peptide (CNP). Furthermore, vascular responses to short and prolonged infusions were compared to investigate rapid hyporesponsiveness of guanylyl-cyclase type A receptor.Methods: In 11 healthy volunteers, arterial response to continuous intra-arterial infusion of ANP (60 pmol/100 mL forearm tissue volume [FAV]/min) was assessed by venous occlusion plethysmography. Then, co-infusion of a similar dose of ANP, BNP, or CNP was administered in randomized order. Each infusion phase was followed by a washout period. Then, ANP was restarted, followed by co-infusion of one of the natriureti...