Atrial peptides

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. 

Aonuma S, Kohama Y. Akai K, Komiyama Y, Nakajima S, Wakabayashi M, Makino T Studies on heart. XIX. Isolation of an atrial peptide that improves the rhythmicity of cultured myocardial cell clusters. Chem Pharm Bull (Tokyo) 1980 28 3332-3339. 

Aonuma S, Kohama Y, Makino T, Hattori K Studies on heart. XXII. Inhibitory effect of an atrial peptide on several drug-induced arrhythmias in vivo. Yakugaku Zasshi 1983 103 662-666. 

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. 

S. P. Adams (Monsanto Compay) and P. Needleman (Washington University, St. Louis) synthesized the following atrial peptides by the solid-phase method 2071 (Table 4). 

Other sequences are N-terminal truncated versions of this peptide (22,28, 31,32 residues)107 Currie at l. have purified two atrial peptides (atriopeptins I and II) of 21 and 23 amino acids.The longer of these is identical to the 10-32 fragment of J. Kangawa and Matsuo have isolated ANF from human atria and determined the amino acid sequence of a 28 amino acid peptide which differs from the rat ANF sequence only at position 17 where He is replaced by Met.106 Based on the sequence discovered by Seidah al., 1 ° synthetic material was made and the important confirmation of the natural material was obtained. The synthetic peptide composed of the 8-33 sequence of Seidah al. has full biological activity.107... 

While predictions are generally not to be trusted, it would still be surprising if the atrial peptides turned to be not just the first but also the last compounds with... 

T.G. Flynn, M.L. de Bold, A.J. de Bold, The amino acid sequence of an atrial peptide with potent diuretic and natriuretic properties. Biochem. Biophys. Res. Commun. 117 859-865 (1983) M.G. Currie, D.M. Geller, B.R. Cole, N.R. Siegel, K.F. Fok, S.P. Adams, S.R. Eubanks, C.R. Galluppi, P. Needleman, Purification and sequence analysis of bioactive atrial peptides (atriopeptines). Science 223 67-69 (1984)... 

Natriuretic Peptide Diuretics. Atrial natriuretic peptide (ANP), an endogenous diuretic, natriuretic, and vasodilator, is a peptide hormone primarily synthesized and stored by atrial cardiocytes, and secreted by the atria in response to mechanical stretch of the atria. It was discovered in the cmde extracts of atria in 1981 (51). ANP is also known as anaritide [95896-08-5] atrial natriuretic factor [104595-79-1] (ANF) auriculin ... 

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... 

Endothelial cells are the major source of ET-1-synthesis. ET-1 is also produced by astrocytes, neurons, hepatocytes, bronchial epithelial cells, renal epithelial and mesangial cells. Physiological stimuli of ET-1-synthesis in endothelial cells are angiotensin II, catecholamines, thrombin, growth factors, insulin, hypoxia and shear stress. Inhibitors of ET-1 synthesis are atrial natriuretic peptide, prostaglandin E2 and prostacyclin. ET-2 is mainly synthesized in kidney, intestine, myocardium and placenta and ET-3 is predominantely produced by neurons, astrocytes and renal epithelial cells. 

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. 

Urodilatin is a peptide similar to atrial natriuretic peptide, which is produced in the distal tubule of the kidney and promotes sodium excretion and diuresis by acting on receptors localized on the luminal site of the collecting duct of the nephron. 

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-... 

ANAb Anti-nuclear antibodies ANCA Anti-neutrophil cytoplasmic auto antibodies cANCA Cytoplasmic ANCA pANCA Perinuclear ANCA AND Anaphylactic degranulation ANF Atrial natriuretic factor ANP Atrial natriuretic peptide Anti-I-A, Anti-I-E Antibody against class II MHC molecule encoded by I-A locus, I-E locus, anti-lg Antibody against an immunoglobulin... 

Atrial natriuretic peptide A type of peptide, 28 amino acids in length, secreted by the atria of the heart when atrial pressure and stretch are increased. 

Nussberger, J., Mooser, V., Maridor, G., Juillerat, L., Waeber, B. and Brunner, H., Caffeine-induced diuresis and atrial natriuretic peptides. J Cadiovasc Pharmacol 15(5), 685-691, 1990. 

Substances released by the heart as atrial natriuretic peptide (ANP) have also offered a new dimension when looking at regulators of circulation (see Sect. 5.2.3) (Y2). 

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). 

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