ABSTRACT
The natriuretic peptides (NPs) collectively constitute a family of hormonal peptides that play important roles in the control of renal, cardiovascular, and skeletal homeostasis. Atrial natriuretic peptide (ANP), the first member of the group to be identified, is a 28-amino peptide in humans that assumes a hairpin structure by virtue of a cysteine bridge linking residues 7 and 23 (Figure 22.1). This hairpin structure typifies each of the natriuretic peptides. It is conserved across species and is required for functional activity. Brain natriuretic peptide (BNP), also known as the B-type natriuretic peptide, is 32 amino acids long in the human. It demonstrates considerably more heterogeneity across species than ANP. CNP is a 22-amino acid peptide which has a truncated carboxy-terminus distal to the second cysteine residue in the bridge.
