Urocortin 2 and urocortin 3 are expressed by the human placenta, deciduas, and fetal membranes.
OBJECTIVE
Urocortin 2 (UCN2) and urocortin 3 (UCN 3) are recently identified neuropeptides showing homology to corticotropin-releasing factor (CRF). In the present study, we evaluated their expression and localization in gestational tissues (placenta, decidua, fetal membranes), and their effect on placental adrenocorticotropic hormone secretion.


METHODS
The study was performed in a tertiary clinical care center. Tissues were obtained at first (n = 8; 8-11 weeks of pregnancy) and third (n = 8; 38-40 gestational weeks) trimester. The mRNA expression was evaluated by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR); the cellular localization by immunohistochemistry; ACTH levels were measured in media collected from cultured placental villi.


RESULTS
All tissues analyzed expressed UCN2 and UCN3 mRNA. UCN2 and UCN3 were localized in cytotrophoblast and syncytiotrophoblast cells; UCN2 was present in maternal and fetal vessels and in amniotic cells, while UCN3 was absent. Finally, UCN2 and UCN3 did not stimulate ACTH secretion.


CONCLUSIONS
Gestational tissues differentially express UCN2 and UCN3 and, despite their homology to CRF, they did not stimulate placental ACTH secretion.
Imperatore
Alberto
A
Department of Pediatrics, Obstetrics and Reproductive Medicine, Section of Obstetrics and Gynecology, University of Siena, Siena, Italy.
Florio
Pasquale
P
Torres
Paulo B
PB
Torricelli
Michela
M
Galleri
Letizia
L
Toti
Paolo
P
Occhini
Rossella
R
Picciolini
Enrico
E
Vale
Wylie
W
Petraglia
Felice
F
D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D002824:Chorionic Villi / Q000378:metabolism; D003346:Corticotropin-Releasing Hormone / Q000096:biosynthesis*; D003656:Decidua / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism; D005321:Extraembryonic Membranes / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D012333:RNA, Messenger / Q000378:metabolism; D014327:Trophoblasts / Q000378:metabolism; D054832:Urocortins
D012333:RNA, Messenger; C426705:UCN2 protein, human; C426704:UCN3 protein, human; D054832:Urocortins; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone