NOVEL PEPTIDES HAVING LIGAND ACTIVITIES ON APJ THAT IS AN ORPHAN G PROTEIN-COUPLED RECEPTOR, AND USE THEREOF

The present invention relates to novel peptide derivatives, which are recognized as ligands to G-coupled protein receptor proteins.The peptide of the present invention can be used in (1) development of a receptor binding assay system using the expression system of the recombinant receptor protein and screening of candidates for pharmaceutical compounds, and (2) development of pharmaceutical preparations such as a neutral nerve function regulator, a circulatory function regulator, a cardiac function regulator, an immune function regulator, a digestive organ function regulator, a metabolic function regulator, a generative organ regulator or the like.