Atrial natriuretic peptide structure

The atrial natriuretic peptide (ANP) belongs to a family of hormones that have structural similarity and some biological actions in common, such as natriuresis and haemoconcentration. It is synthesized and secreted by the cardiac atrium in response to increased atrial pressure. ANP is believed to act physiologically in an opposing manner to AVP... 

The atria and other tissues of mammals contain a family of peptides with natriuretic, diuretic, vasorelaxant, and other properties. The family includes atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP). The peptides share a common 17-amino-acid disulfide ring with variable C- and N-terminals (Figure 17-5). A fourth peptide, urodilatin, has the same structure as ANP with an extension of four amino acids at the N-terminal. 

Structures of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). Sequences common to the peptides are indicated in green. 

In 1983 de Bold et al. 202) first isolated an atrial peptide ANP-(6-33) from homogenates of rat atrial muscle and elucidated its structure (Fig. 14). In January 1984, K. Kangawa et al. prepared pure samples of the a-human atrial natriuretic peptide a-h-ANP-(6-33 Met17) 203) and of the hitherto longest-known natriuretic peptide containing 126 amino acids, y-h-ANP 204), from human atrial tissue. 

Von Geldern TW, Rockway TW, Davidsen SK, Budzik GP, Bush EN, Chu-Moyer MY, Devine EM Jr, Holleman WH, Johnson MC, Lucas SD, Pollock DM, Smital JM, Thomas AM, Opgenorth TJ. Small atrial natriuretic peptide analogs design, synthesis, and structural requirements for guanylate cyclase activation. J. Med. Chem. 1992 35 808-816. 

Several hues of evidence confirmed the cardiomyocyte nature of the cells within the beating EBs (Fig. 12.2) [40]. Reversed-phase polymerase chain reaction (RT-PCR) studies demonstrated the expression of cardiac-specific transcription factors (e.g., GATA4 and Nkx2.5) and cardiac-specific structural genes [cTnl, cTnT, atrial natriuretic peptide (ANP), MLC-2V, MLC-2a]. Initial analysis of gene expression pattern during in vitro cardiomyocyte differentiation of the hES revealed a reproducible... 

Physiologists had postulated for a long time about the existence of a sodium excreting hormone to prevent Na overload and consequent deleterious effects of high blood pressure on the heart and vascular system. At least two such natriuretic factors have been described atrial or A-type and brain or B-type natriuretic factors. Structurally, the natriuretic factors are peptides with a cysteine-cysteine disulfide bridge creating a characteristic loop , this is illustrated by Figure 8.8. 

Inhibition of NEP also prevents the degradation of atrial natriuretic factor (ANF), a natural hypotensive peptide. Dual inhibitors of NEP and ACE have been designed successfully because both enzymes share significant structural homology, particularly in their active sites. Simultaneous inhibition of both peptidases produces a more powerful hypoten-... 

Quirion R, Dalpe M, De Lean A. Gutkowska J. Cantin M, Genest J. Atrial natriuretic factor (ANF) binding sites in brain and related structures. Peptides 1984 5 1167-1172. 

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