title: Isolation of a human seminal plasma peptide with bombesin-like activity.
abstract: Bombesin (BN) and BN-like peptides such as gastrin-releasing peptide (GRP) belong to the growing group of regulatory peptides. Bombesin and GRP share the same carboxyl-terminal heptapeptide sequence that is essential for receptor recognition and biologic activity. Immunohistochemical findings have indicated the presence of a BN-like peptide in the neuroendocrine cells of the human prostate. These findings, together with the high concentrations of different regulatory peptides recently found in seminal plasma, prompted us to characterize a BN-like peptide in human semen by gel-filtration chromatography, reverse-phase high-pressure liquid chromatography, and in vitro bioassay. Here we demonstrate that human semen contains high levels (mean +/- standard deviation, 288.9 +/- 114.39 pg/ml) of a substance that closely resembles the 14-27 carboxyl-terminal fragment of GRP (GRP 14-27). The partially purified peptide obtained from this source, examined on an in vitro bioassay that is especially useful for testing BN-like activities, elicits a contractile response of the rat uterus that is indistinguishable from that stimulated by standard BN and GRP 14-27. The GRP 14-27 present in human seminal plasma may be involved in some aspect of the process of fertilization.
authors.affiliation: Department of Andrology, University of Rome La Sapienza, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Gnessi
authors.forename: S
authors.initials: S
authors.lastname: Ulisse
authors.forename: A
authors.initials: A
authors.lastname: Fabbri
authors.forename: E A
authors.initials: EA
authors.lastname: Jannini
authors.forename: V
authors.initials: V
authors.lastname: Bonifacio
authors.forename: C
authors.initials: C
authors.lastname: Moretti
authors.forename: G
authors.initials: G
authors.lastname: Spera
authors.forename: A
authors.initials: A
authors.lastname: Isidori
mesh_terms: D000328:Adult; D000818:Animals; D001839:Bombesin / Q000302:isolation & purification*; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005260:Female; D019886:Gastrin-Releasing Peptide; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D010455:Peptides / Q000302:isolation & purification* / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D012016:Reference Values; D012661:Semen / Q000032:analysis*; D014590:Uterine Contraction / Q000187:drug effects
chemical_list: D010455:Peptides; D019886:Gastrin-Releasing Peptide; D001839:Bombesin