Prolactin Releasing Peptide (1-31), human is a high affinity GPR10 ligand that cause the release of the prolactin. Prolactin Releasing Peptide (1-31) binds to GPR10 for human and rats with Ki values of 1.03 nM and 0.33 nM, respectively. Prolactin Releasing Peptide (1-31) can be used for the research of the hypothalamo-pituitary axis.