Natriuretic Peptide B is synthesized as a 134 residue preprohormone before a signal peptide is cleaved, creating a storage protein which is further cleaved into the 32 residue, biologically active peptide that is secreted into the blood. NPPB was first discovered in porcine brain, but is produced mainly by cardiac ventricle cells in humans. It acts as a cardiac hormone with a variety of functions including natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion. Additionally, it plays a key role in cardiovascular homeostasis, helps restore the body's salt and water balance, and improves heart function. NPPB also has antimicrobial properties against Gram-positive and Gram-negative bacteria as well as yeast in a dose-dependent manner.