Physiology and Pathophysiology of the Natriuretic Peptide System

Abstract

The natriuretic peptide family consists of four structurally similar but genetically distinct peptides with unique biochemical and physiologic properties (Table 1). In 1981, de Bold and colleagues infused atrial homogenate extracts into rats and noted massive diuresis and natriuresis [1]. The structure of atrial natriuretic peptide (ANP), the peptide hormone responsible for these actions, was identified by Kangawa and Matsuo in 1984 [2]. Four years later, another peptide with natriuretic and diuretic properties similar to ANP was identified in extracts of porcine brain [3]. Although this 32-amino acid polypeptide was called brain natriuretic peptide (BNP), it was soon determined that that the primary site of BNP synthesis was in the ventricular myocardium [4]. Since then, additional members of the natriuretic peptide family of extracardiac origin have been identified:

• C-type natriuretic peptide (CNP) is a 22-amino acid peptide mainly present in the central nervous system (CNS) and vascular endothelial cells with very low concentrations in human plasma 5.

• The fourth member of the natriuretic peptide family is dendroaspis natriuretic peptide (DNP), isolated from the venom of the green mamba snake with structural similarity to ANP, BNP, and CNP [6]. It has also been reported that DNP-like immunoreactivity is present in human plasma and in the atrial myocardium [7].