NPPA also known as ANP, ANF belongs to the natriuretic peptide family. NPPA plays a crucial role in regulating blood pressure and fluid balance within the body, primarily by promoting natriuresis, which is the excretion of sodium through urine. This function is vital for maintaining electrolyte homeostasis and preventing conditions such as hypertension and heart failure. NPPA is secreted by cardiac atrial cells in response to increased blood volume and pressure, acting as a counter-regulatory mechanism to the renin-angiotensin-aldosterone system. NPPA′s structure features a unique 17-residue ring formed by an intramolecular disulfide bond, which is essential for biological activity and receptor binding.