Neurokinin B (human, porcine) is a tachykinin agonist peptide that shows preference for the NK3 receptor, with an EC50 of 1 nM. Neurokinin B (human, porcine) is an important endogenous neuropeptide and contributes to luteinizing hormone secretion, the estrous cycle, energy balance, dynamics of fetus in placenta, and contraction in uterine muscles of rat. Loss of function mutations in the genes encoding either neurokinin B or its receptor, NK3 result in hypogonadotropic hypogonadism, implicating NKB and NK3 as essential elements of the human reproductive axis.
