BNP (1-32), human

Basic natriuretic peptide (BNP), now known as B-type natriuretic peptide (also BNP) or GC-B, is a 32 amino acid polypeptide secreted by the ventricles of the heart in response to excessive stretching of heart muscle cells (cardiomyocytes). The release of BNP is modulated by calcium ions¹. BNP is named as such because it was originally identified in extracts of porcine brain, although in humans it is produced mainly in the cardiac ventricles. The physiologic actions of BNP are similar to ANP and include decrease in systemic vascular resistance and central venous pressure as well as an increase in natriuresis. Thus, the net effect of BNP and ANP is a decrease in blood volume which lowers systemic blood pressure and afterload, yielding an increase in cardiac output, partly due to a higher ejection fraction. The main clinical utility of either BNP or NT-BNP is that a normal level rules out acute heart failure in the emergency setting². Recombinant BNP, Nesiritide is used to treat decompensated heart failure³.

References:
1. Ziskoven D, Forssmann WG, Holthausen U, Menz G, Addicks K, Rippegater G: Calcium Calmodulinantagonists Influences the release of Cardiodilatin/ANP from Atrial Cardiocytes. Handbook Endocrinology of the Heart, edited by Kaufmann W, Wambach G, 01/1989; Springer Verlag Berlin Heidelberg New York;
2. Maisel A, Krishnaswamy P, Nowak R, McCord J, Hollander J, Duc P, Omland T, Storrow A, Abraham W, Wu A, Clopton P, Steg P, Westheim A, Knudsen C, Perez A, Kazanegra R, Herrmann H, McCullough P (2002). "Rapid measurement of B-type natriuretic peptide in the emergency diagnosis of heart failure". N Engl J Med 347 (3): 161–7.
3. O'Connor CM, Starling RC, Hernandez AF, et al. Effect of nesiritide in patients with acute decompensated heart failure. TheNew Englandjournal of medicine 2011;365:32-43.