The natriuretic peptide inhibits the renal reabsorption of sodium decreases through the collecting duct, which produces urine. The general effect of ANP in the body is to combat the increase in blood pressure and volume caused by the renin-angiotensin system. Natriuretic peptides: PNA, released, in atria and ventricles; PNB, released, in ventricles and brain and; PNC, released in the endothelium of renal, coronary and pulmonary vessels, is also a selective vasodilator, independent of the endothelium. Natriuretic peptides exert their biological effects by binding to specific receptors on endothelial, epithelial, and smooth muscle vascular cell surfaces.