Prolactin (also known as mammotrophin，luterotropic hormone，and lutetropin) is a neuroendocrine hormone secreted by the pituitary gland. Its primary function is to promote and maintain lactation during pregnancy and suckling. In addition，Prolactin plays an immune-regulatory role by stimulating the activities of ornithine decarboxylase and protein kinase C，which are important for the proliferation，differentiation，and function of lymphocytes. Recombinant human Prolactin is a 23 kDa globular protein containing 200 amino acid residues.
