Cardiac hormone that plays a key role in mediating cardio-renal homeostasis. May also function as a paracrine antifibrotic factor in the heart. Acts by specifically binding and stimulating NPR1 to produce cGMP, which in turn activates effector proteins that drive various biological responses. Involved in regulating the extracellular fluid volume and maintaining the fluid-electrolyte balance through natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion. Binds the clearance receptor NPR3.; Plays a key role in cardiovascular homeostasis through natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion. In vivo, induces vasodilation.; May affect cardio-renal homeostasis. Able to promote the production of cGMP although its potency is very low compared to brain natriuretic peptide 32.