Brain natriuretic peptide-32 (BNP-32), a fragment of the proBNP cardiovascular hormone precursor, exhibits affinity for natriuretic peptide receptors in rat vascular smooth muscle cells (IC50 = 7.3 nM) and promotes cGMP accumulation within these cells (EC50 = 170 nM). Additionally, BNP-32 effectively mediates the relaxation of norepinephrine-precontracted isolated rat aortic strips (EC50 = 6.7 nM). Upon administration at a dosage of 3 µg/kg, it elevates urine and urinary electrolyte outputs and induces hypotension in rats.