Kisspeptin-54 (human) (Metastin (human) ) is an endogenous ligand for kisspeptin receptor (KISS1, GPR54) . Kisspeptin-54 (human) binds to rat and human GPR54 receptors with Ki values of 1.81 nM and 1.45 nM, respectively. Kisspeptin-54 (human) inhibits tumor metastasis and stimulates the secretion of gonadotropin (LH) and testosterone[1][2][3][4][5][6][7][8].