Functional multiplicity of atrial natriuretic peptide receptors on cultured rat Leydig tumor cells

Native rat atrial natriuretic peptide (NANP) was shown to bind with high affinity and to increase intracellular levels of cGMP in cultured rat Leydig tumor cells. A linear analog of NANP which lacks the disulfide-linked bridge structure also bound with high affinity but did not increase levels of intracellular cGMP or antagonize the increase of this cyclic nucleotide by NANP. These data are consistent with the existence of two functional subpopulations of ANP receptors on cultured rat Leydig tumor cells; one which is capable of activating guanylate cyclase and one which is not linked to this enzyme.