“…Many neuropeptides, such as thyrotropin-releasing hormone (TRH), vasopressin, neurotensin, galanin and the recently discovered PRL-releasing peptide (PrRP) could promote PRL release from pituitary (Lamberts and MacLeod, 1990;Ben-Jonathan and Liu, 1992;Hammond et al, 1996;Hinuma et al, 1998). In turn, release of β-END -proopiomelanocortin (POMC) processing product, co-released with ACTH -is mainly enhanced by corticotropin-releasing hormone (CRH), as well as by substance P, cholecystokinine (CCK), vasopressin, oxytocin (OT) and vasoactive intestinal peptide (VIP) (Matsumura et al, 1982(Matsumura et al, , 1983Sweep and Wiegant, 1989;Bogacka et al, 2002a). Catecholamines and gonadotrophinreleasing hormone (GnRH) are other candidates, which may influence pituitary PRL and β-END secretion (Denef and Baes, 1982;Gambacciani et al, 1988;Kerdelhue et al, 1988;Shin and Barton, 1993;Denef, 1994;Colthorpe et al, 2000).…”