A 71915 is a highly potent and competitive natriuretic peptide receptor A (ANP, NPRA) antagonist (pKi= 9.18). A 71915 displaces [¹²⁵I]ANP dose dependently, with a Ki of 0.65 nM. A71915( pA2= 9.48) against rat ANP-induced cGMP production in NB-OK-1 cells.