title: Increase of the trophoblast giant cells with prolactin-releasing peptide (PrRP) receptor expression in p53-null mice.
abstract: Trophoblast giant cells in the mouse placentas are polyploid cells that form as a result of endoreduplication. The giant cells form the outermost layer of the extraembryonic compartment and produce a number of pregnancy-specific hormones, including prolactin family members. Here we demonstrate that trophoblast giant cells are increased, and display upregulation of prolactin releasing peptide (PrRP) receptor in the p53-null (p53(-/-)) embryonic placentas. At day 13.5 of gestation, the weight of p53(-/-) placentas was less than that of both wild-type and p53(+/-) placentas. In p53(-/-) placentas, the spongiotrophoblast layer was significantly decreased in thickness, and the trophoblast giant cells were observed not only in the outer layer of placentas but in both the spongiotrophoblast layer and the labyrinthine layer. The giant cells spread over the spongiotrophoblast and labyrinthine layer in p53(-/-) placentas displayed more intensive expression of immunoreactive PrRP receptor than in wild-type placentas. Previous studies indicated that the association between PrRP and PrRP receptor physiologically involves in the expression and secretion of the peptide hormones, including prolactin and growth hormones. These results suggest that p53 may regulate the differentiation of trophoblast giant cells, and may control the physiological PrRP stimuli in mouse placentas.
authors.affiliation: Department of Neurosurgery, School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Komatsu
authors.forename: Takumi
authors.initials: T
authors.lastname: Abe
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sano
authors.forename: Kiyoe
authors.initials: K
authors.lastname: Shimazaki
authors.forename: Motowo
authors.initials: M
authors.lastname: Tomita
authors.forename: Naohiro
authors.initials: N
authors.lastname: Kanayama
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D002452:Cell Count; D005260:Female; D015726:Giant Cells / Q000737:chemistry / Q000378:metabolism*; D007028:Hypothalamic Hormones / Q000032:analysis / Q000378:metabolism*; D051379:Mice; D008817:Mice, Mutant Strains; D009479:Neuropeptides / Q000032:analysis / Q000378:metabolism*; D010920:Placenta / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D056690:Prolactin-Releasing Hormone; D014327:Trophoblasts / Q000737:chemistry / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology*; D015854:Up-Regulation
chemical_list: D007028:Hypothalamic Hormones; D009479:Neuropeptides; C534378:Prlh protein, mouse; D056690:Prolactin-Releasing Hormone; D016159:Tumor Suppressor Protein p53