Myometrial contractility influences oxytocin receptor (OXTR) expression in term trophoblast cells obtained from the maternal surface of the human placenta

• Published in: BMC pregnancy and childbirth 2015-09, Vol.15 (1), p.220-220, Article 220
• Main Authors: Szukiewicz, Dariusz, Bilska, Anna, Mittal, Tarun Kumar, Stangret, Aleksandra, Wejman, Jaroslaw, Szewczyk, Grzegorz, Pyzlak, Michal, Zamlynski, Jacek
• Format: Article
• Language: English
• Subjects: Adult; Cesarean Section; Chemical bonds; Female; Humans; Infant, Newborn; Kinases; Ligands; Oxytocin - metabolism; Placenta; Placenta - cytology; Pregnancy; Proteins; Receptors, Oxytocin - metabolism; Signal Transduction - physiology; Term Birth - metabolism; Trophoblasts - metabolism; Uterine Contraction - physiology
• ISSN: 1471-2393; 1471-2393
• DOI: 10.1186/s12884-015-0656-3

Oxytocin (OXT) acts through its specific receptor (OXTR) and increased density of OXTR and/or augmented sensitivity to OXT were postulated as prerequisites of normal onset of labor. Expression of OXTR in the placental term trophoblast cells has not yet been analyzed in the context of contractile activity of the uterus. Here we examine comparatively OXT contents in the placental tissue adjacent to the uterine wall and expressions of OXTR in this tissue and corresponding isolated placental trophoblast cells. Twenty eight placentae after normal labors at term (group I, N = 14) and after cesarean sections performed without uterine contractile activity (group II, N = 14) have been collected. Tissue excised from the maternal surface of examined placenta was used for OXT concentration measurement, cytotrophoblast cell cultures preparation and immunohistochemistry of OXTR. Concentration of OXT was estimated in the tissue homogenates by an enzyme immunoassay with colorimetric detection. Cytotrophoblast cells were isolated using Kliman's method based on trypsin, DNase, and a 5-70% Percoll gradient centrifugation. The cultures were incubated for 5 days in normoxia. Both placental specimens and terminated cytotrophoblast cultures were fixed and embedded in paraffin before being immunostained for OXTR. Using light microscopy with computed morphometry for quantitative analysis, OXTR expressions were estimated in calibrated areas of the paraffin sections. There were not significant differences between the groups in respect to the mean OXT concentration. However, in both groups the median value of OXT concentration was significantly (p