Natriuretic peptide family

In addition to its pump function, the heart is also a secretory organ. Cardiac cells produce two small peptides, the natriuretic factors, which oppose the vasoconstrictive actions of noradrenaline (norepinephrine) from the sympathetic nervous system and of the peptide angiotensin II. By causing vasodilation and natriuresis (increased excretion of sodium in the urine), atrial natriuretic peptide (ANP) secreted from the atria and B-type natriuretic peptide (BNP) secreted by both atria and probably more significantly, from the ventricles, reduce blood pressure. The stimulus to secretion of natriuretic peptides is wall stretch of the chambers of the heart, indicating volume and pressure overload of the vascular system. A third member of the natriuretic peptide family, CNP, is secreted by endothelial cells. 

Natriuretic peptides are naturally occurring substances in the body that oppose the activity of the renin-angiotensin system. The natriuretic peptide family consists of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). All three natriuretic peptides are synthesized from cleavage of a larger precursor polypeptide. In the ventricles and brain, the synthesis of BNP predominates ANP is synthesized by cardiac myocytes predominately in the atria and CNP is synthesized in the brain, blood vessels, and kidney. 

Sudoh T, Minamino N, Kangawa K, Matsuo H (1990) C-type natriuretic peptide (CNP) a new member of natriuretic peptide family identified in porcine brain. Biochem Biophys Res Commun 168 863-70... 

C-type natriuretic peptide (CNP) the newest member of the natriuretic peptide family, was first isolated from porcine brain, and later found in other mammals and nonmammals. It is processed from a pre-pro-CNP molecule, which gives rise to CNP-22 and its N-terminally elongated form. CNP-53. The CNP s share considerable sequence homology with atrial NATRIURETIC PEPTIDES (ANP) and brain natriuretic peptides (BNP). CNP s are atrial NATRIURETIC PEPTIDE RECEPTOR AGONISTS but are more active at the type-B subtype, whereas ANP s are more active at the type-A subtype. 

The natriuretic peptide family has three members, atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), and C-type natriuretic peptide (CNP). ANP is stored mainly in the right atrium, whereas BNP is found mainly in the ventricles. Both are released in response to pressure or volume overload. CNP is found mainly in the brain and has very low plasma concentrations. ANP and BNP plasma concentrations are elevated in patients with heart failure and are thought to balance the effects of the RAA system by causing natriuresis, diuresis, vasodilation, decreased aldosterone release, decreased hypertrophy, and inhibition of the SNS and the RAA system. 

Ceo, L. B. 2005. Natriuretic peptide family New aspects. Current Medical Chemistry Cardiovascular Hematology Agents 3 87-98. 

Suga S, Nakao K, Hosoda KJ, Mukoyama M, Ogawa Y, Shirakami G et al. Receptor selectivity of natriuretic peptide family, atrial natriuretic peptide, brain natriuretic peptide, and C-type natriuretic peptide. Endocrinology 1992 130 229-239. 

Atrial Natriuretic Peptide, a-Atrial natriuretic peptide [85637-73-6] (ANP) (55), also known as atrial natriuretic factor (ANF), brain natriuretic peptide (BNP) (56), and type C natriuretic peptide (CNP) (57) are members of the ANP family (28). These atrial peptides arise from a common 128 amino acid precursor where the active form of ANP is the 28 amino acid peptide at the C terminus. 

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... 

Natriuretic peptides are a family of peptide hormones. All of them contain a 17-amino acid long ring that is closed by a disulfide bond between two cysteine residues. ANP (atrial natriuretic peptide) is mainly expressed in the atria of the heart, whereas BNP (B-type natriuretic peptide) is synthesized in the ventricular myocardium. CNP occurs mainly in the endothelium and is thought to have a paracrine function. ANF and BNF lower blood pressure by a direct effect on smooth muscle and on the salt retention in the kidney. Natriuretic peptides bind and activate particulate guanylyl cyclases. 

Atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP) are members of a family of so-called natriuretic peptides, synthesized predominantly in the cardiac atrium, ventricle, and vascular endothelial cells, respectively (G13, Y2). ANP is a 28-amino-acid polypeptide hormone released into the circulation in response to atrial stretch (L3). ANP acts (Fig. 8) on the kidney to increase sodium excretion and glomerular filtration rate (GFR), to antagonize renal vasoconstriction, and to inhibit renin secretion (Ml). In the cardiovascular system, ANP antagonizes vasoconstriction and shifts fluid from the intravascular to the interstitial compartment (G14). In the adrenal cortex, ANP is a powerful inhibitor of aldosterone synthesis (E6, N3). At the hypothalamic level, ANP inhibits vasopressin secretion (S3). It has been shown that some of the effects of ANP are mediated via a newly discovered hormone, called adreno-medullin, controlling fluid and electrolyte homeostasis (S8). The diuretic and blood pressure-lowering effect of ANP may be partially due to adrenomedullin (V5). 

ANP now belongs to a family of natrinreteic peptides that also includes BNP (brain natrinretic peptide) and CNP (C-type natriuretic peptide). BNP and CNP have different N- and C-termini to ANP. CNP has a shorter N-terminal than either ANP or BNP. CNP has less natriuretic and diuretic activity than ANP or BNP. 

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. 

Cyclic nucleotide regulated protein kinase family = Adenylyl cyclases = A-kinase anchor proteins = Atypical PKCs = Atrial natriuretic peptide = Adenosine 5 -triphosphate = Brain natriuretic peptide = Ca Vcalmodulin-dependent kinases = Cyclin-dependent kinases = Ca -dependent protein kinase = Casein kinase I = Casein kinase II = Dcd-like kinase... 

Natriuretic peptides (NP) are secreted to regulate fluid volume, blood pressure, and electrolyte balance. They have activity in both the central and peripheral nervous systems. ANP was the first described in 1981. BNP was discovered 7 years later in the porcine brain, thus the name. However, in humans, while produced in the brain, the main source of circulatory BNP is the heart ventricles. Other members of the NP family include C-type natriuretic peptide (CNP) and urodilatin. Although these two hormones are not produced by myocardium, they are released with ANP and BNP in patients with volume overload, hypertension, and hyponatremia. 

NESIRITIDE Nesiritide (natrecor), a recombinant form of human brain natriuretic peptide (BNP), is FDA-approved for treatment of dyspnea due to congestive heart failure. The natriuretic peptides—atrial natriuretic peptide (ANP), BNP, and C-type natriuretic peptide—are a family of endogenous hormones that possess potent natriuretic, diuretic, and vasodilator properties. BNP is secreted by ventricular cardiac myocytes in response to stretch circulating levels of BNP correlate with the severity of heart failure. In the setting of heart failure, the effects of BNP counteract the effects of Angll and NE by producing vasodilation, natriuresis, and diuresis. 

Cyclic GMP is made from GTP by the enzyme gua-nylyl cyclase, which exists in soluble and membrane-bound forms. Each of these isozymes has unique physiologic properties. The atriopeptins, a family of peptides produced in cardiac atrial tissues, cause natriuresis, diuresis, vasodilation, and inhibition of aldosterone secretion. These peptides (eg, atrial natriuretic factor) bind to and activate the membrane-bound form of guanylyl cyclase. This results in an increase of cGMP by as much as 50-fold in some cases, and this is thought to mediate the effects mentioned above. Other evidence links cGMP to vasodilation. A series of compounds, including nitroprusside, nitroglycerin, nitric oxide, sodium nitrite, and sodium azide, all cause smooth muscle re-... 

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