B-type natriuretic peptide

Because renal vasodilatation and hyperfiltration are often associated with a natriuretic response, a number of activators or inhibitors of endogenous vasoactive systems can cause increased NaCl excretion, and some of these may be developed into compounds of clinical interest in special situations. Such agents include natriuretic pqDtides most notably B-type natriuretic peptide (nesiritide), neutral endopeptidase (NEP) inhibitors (thiorphan, phosphoramidon), mixed NEP and ACE inhibitors (omapatrilat), guanylin and uroguanylin, kinins, prostaglandins of the E series, adrenomedullin, relaxin, prolactin, and others. 

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. 

BNP, B-type natriuretic peptide BP, blood pressure ECC, electrocardiogram HR, heart rate. 

Nesiritide is manufactured using recombinant techniques and is identical to the endogenous B-type natriuretic peptide secreted by the ventricular myocardium in response to volume overload. Consequently, nesiritide mimics the vasodilatory and natriuretic actions of the endogenous peptide, resulting in venous and arterial vasodilation increases in cardiac output natriuresis and diuresis and decreased cardiac filling pressures, sympathetic nervous system activity, and renin-angiotensin-aldosterone system activity. 

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. 

Richards AM, Lainchbury JG, Troughton RW, et al. Clinical applications of B-type natriuretic peptides. Trends Endocrinol Metabol 2004 15 170. ... 

E. coli expressed recombinant human B-type natriuretic peptide (hBNP]... 

In addition to these traditional vasodilators, nesir-itide (Natrecor) was developed as a newer method for producing arterial and venous dilation in people with heart failure.58 This substance was derived from human B-type natriuretic peptide (BNP) using recombinant DNA techniques. BNP is a naturally occurring substance that is released from the ventricles when the heart is subjected to increased blood volume and pressure.12 This substance dilates peripheral arteries and veins, thus reducing cardiac afterload and preload, respectively. Hence, nesiritide can be administered intravenously to reduce cardiac workload in certain patients with severe or acute heart failure.12,58... 

Burger AJ. A review of the renal and neurohormonal effects of B-type natriuretic peptide. Congest Heart Fail. 2005 11 30-38. 

Mega JL, Morrow DA, deLemos JA, et al, B-type natriuretic peptide at presentation and prognosis in patients with ST segment elevation myocardial infarction, J Am Coll Cardiol 2004 44 335-339. 

Richards M, Nicholls MG, Espiner EA, etal. Comparison of B-type natriuretic peptides for assessment of cardiac function and prognosis in stable ischemic heart disease. J Am Coll Cardiol 2006 47 52-60. 

Heeschen C, Hamm CW, MhrovicV etal. N-terminal pro-B-type natriuretic peptide levels for dynamic risk stratification of patients with acute coronary syndromes. Circulation 2004 ... 

Morrow DA, deLemos JA, Blazing MA, et al. Prognostic value of serial B-type natriuretic peptide testing during follow-up of patients with unstable coronary artery disease. J Am Med Assoc 2005 294 2866-2871. 

Figure 5-3. Complete spectrum of acute coronary pathophysiological process from initiation of atherosclerosis to cell death. Biomarkers released at different stages include interleukin 6 (IL-6), myeloperoxidase (MPO), soluble CD40 ligand (sCD40L), high-sensitivity C-reactive protein (Hs-CRP), ischemia-modified albumin (IMA), cardiac troponins I and T (cTnT and cTnl, respectively), B-type natriuretic peptide (BNP), and N-terminal proBNP (NT-proBNP). Of these, only the troponins and BMPs are myocardial specific.

It has been suggested that monitoring B type natriuretic peptide concentrations after anthracycline administration can reflect cardiac tolerance, and through serial monitoring allow a picture of the degree of left ventricular dysfunction to be established (41). 

Suzuki T, Hayashi D, Yamazaki T, Mizuno T, Kanda Y, Komuro I, Kurabayashi M, Yamaoki K, Mitani K, Hirai H, Nagai R, Yazaki Y. Elevated B-type natriuretic peptide levels after anthracycline administration. Am Heart J 1998 136(2) 362-3. 

Burger AJ, Horton DP, LeJemtel T, Ghali JK, Torre G, Dennish G, Koren M, Dinerman J, Silver M, Cheng ML, Elkayam U Prospective Randomized Evaluation of Cardiac Ectopy with Dobutamine or Natrecor Therapy. Effect of nesiritide (B-type natriuretic peptide) and dobutamine on ventricular arrhythmias in the treatment of patients with acutely decompensated congestive heart failure the PRECEDENT study. Am Heart J 2002 144(6) 1102-8. 

Rule In B-type natriuretic peptide (BNP) Is this, breathless patient suffering from heart failure 450ng/L Confirm with cardiac. . ultrasound, decide to . admit and treat Reduced symptoms, decreased. . morbidity and mortality... 

Type 1 question regarding diagnostic accuracy of a test In patients coming to the emergency department with shortness of breath, how well does B-type natriuretic peptide (BNP) or N-terminal pro-BNP predict (identify the presence of) heart failure as assessed by the cardiac ejection fraction measured by echocardiography ... 

B-type natriuretic peptide Peptide with an Vascular, renal, and Regulation of blood volume and... 

Brain (or B-type) natriuretic peptide (BNP) is a hormone that was originally isolated from porcme brain tissue. It has... 

New York Heart Association Class Figure 44-17 Correlation of BNP concentrations (Biosite Triage) according to NYHA classification of heart failure. (From Maisel AS, Krisbnaswamy R Nowak RM, McCord J, Hollander JE, Due R ef al. Rapid measurement of B-type natriuretic peptide in the emergency diagnosis of heart failure. N Engl J Med 2002 347 ... 

Figure 44-19 ROC curves for individual and combined estimated clinical probability for CHF diagnosis based on clinical judgment and BNP monitoring. (From McCullough PA, Nowak RM, McCord J, Hollander JE, Herrmann HC, Steg PG, et al. B-type natriuretic peptide and clinical Judgment in emergency diagnosis of heart failure analysis from breathing not properly (BNP) multinational study. Circulation 2002 106 416-22.)...

Figure 44-20 Risk of death for BNP and NT-proBNP in acute coronary syndrome patients according to baseline plasma concentrations. (Pane A, from de LemosJA, Morrow DA, Bentley JH, OmiandT, Sabatine MS, McCabe CH, et al.Tbe prognostic value of B-type natriuretic peptide in patients with acute coronary syndromes. N Engl J Med 2001 345 1014-21. Panel 6, from OmIandT, PerssonA, Ng L, O Bnen R, Kar/sson T, Herlitz j, et al. N terminal pro-B-type natriuretic peptide and long term mortality in acute coronary syndromes. Circulation 2002 /06 29/3-S.)...

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