For which is cGMP second messenger?

The binding of ANP to its receptor causes the conversion of GTP to cGMP and raises intracellular cGMPAs a consequence, cGMP activates a cGMP-dependent kinase (PKG or cGK) that phosphorylates proteins at specific serine and threonine residues.In the medullary collecting duct, the cGMP generated in response to ANP may act not only through PKG but also direct modulation of ion channels.Ref: DM Vasudevan, 7th edition, page no: 409