Atrial Natriuretic Factor (1-29), chicken, (C130H223N51O41S5), a peptide with the sequence H2N-SPKMVQGSGCFGRKMDRISSSSGLGCKVLRRH-OH, MW= 3316.8. Atrial natriuretic peptide (ANP), atrial natriuretic factor (ANF), atrial natriuretic hormone (ANH), Cardionatrine, Cardiodilatine (CDD) or atriopeptin, is a powerful vasodilator, and a protein (polypeptide) hormone secreted by heart muscle cells(1). It is involved in the homeostatic control of body water, sodium, potassium and fat (adipose tissue). It is released by muscle cells in the upper chambers (atria) of the heart (atrial myocytes) in response to high blood pressure. ANP acts to reduce the water, sodium and adipose loads on the circulatory system, thereby reducing blood pressure. ANP has exactly the opposite function of the aldosterone secreted by the zona glomerulosa(2). ANP binds to a specific set of receptors – ANP receptors. Receptor-agonist binding causes a reduction in blood volume and therefore a reduction in cardiac output and systemic blood pressure. Lipolysis is increased and renal sodium reabsorption is decreased. The overall effect of ANP on the body is to counter increases in blood pressure and volume caused by the renin-angiotensin system. Neutral endopeptidase (NEP) is the enzyme that metabolizes natriuretic peptides. Several inhibitors of NEP are currently being developed to treat disorders ranging from hypertension to heart failure(3).
Figure1 Formula of Atrial Natriuretic Factor (1-29)
Figure2 signal pathway of Atrial Natriuretic Factor
Ref:
1. Widmaier, Eric P.; Hershel Raff, Kevin T. Strang (2008). Vander's Human Physiology, 11th Ed.. McGraw-Hill. pp. 291, 509–10.
2. Marieb Human Anatomy & Physiology 9th edition, chapter:16, page:629, question number:14
3. Venugopal J (2003). "Pharmacological modulation of the natriuretic peptide system". Expert Opinion on Therapeutic Patents 13 (9): 1389.