ABSTRACT
Oxytocin is a nine amino acid peptide involved in a wide spectrum of physiological functions; predominantly those concerning reproduction and differentiation are of interest. Oxytocin receptors are expressed at early developmental stages of mammals, suggesting that oxytocin might be involved in the determination of the germ stem cell line, at the very early stages of mammalian development. In this respect, the proximate aim of the present study was to confirm and further analyze the existence of oxytocin receptors at a very early level of cell commitment, that is, the determination of germ cells derived from embryoid bodies. To achieve our purpose we have cultured mouse embryonic stem cells under conditions inducing formation of embryoid bodies. In this work, ES cells were allowed to aggregate in a novel medium, "Stefanidis medium" from day 0 to day 14 until formed EBs. RNA was isolated from EBs and using RT-PCR we showed that EBs expressed Oct-4, OTR, OT, and DAZL. To demonstrate simultaneous expression immunocytochemistry was preformed, in which EBs showed strong immunoreactivity for both, OTR and DAZL molecular markers. We found that 35% of the cells displayed OTR, using flow cytometry. In addition, this novel medium showed to increase OTR mRNA. We propose, that at least in murine induced embryoid bodies there is simultaneous expression of oxytocin receptors and germ cell markers (DAZL) in many cells (expressing Oct-4). We thus conclude that, the oxytocin might indeed be a molecule playing a leading role in germ cell determination.
Subject(s)
Embryonic Stem Cells/metabolism , Octamer Transcription Factor-3/genetics , RNA-Binding Proteins/genetics , Receptors, Oxytocin/genetics , Animals , Cell Aggregation , Cell Differentiation , Cells, Cultured , Embryo, Mammalian/cytology , Embryo, Mammalian/embryology , Embryo, Mammalian/metabolism , Embryonic Stem Cells/cytology , Flow Cytometry , Gene Expression Regulation, Developmental , Immunohistochemistry , Mice , Octamer Transcription Factor-3/metabolism , Oxytocin/genetics , Oxytocin/metabolism , RNA-Binding Proteins/metabolism , Receptors, Oxytocin/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time FactorsABSTRACT
OBJECTIVE: To report on a patient with a quintuplet pregnancy consisting of a monochorionic triamnionic triplet pregnancy and one case of monoamniotic twins after intracytoplasmic sperm injection (ICSI), laser-assisted hatching, and day 4 embryo transfer. CASE REPORT: A 34-year-old woman who underwent ICSI due to male infertility. She underwent standard controlled ovarian hyperstimulation. Retrieved oocytes were fertilized in vitro, and 3 embryos were transferred on day 4 after laser-assisted hatching. Transvaginal ultrasound revealed a monoamniotic twin pregnancy and a monochorionic-triamniotic triplet pregnancy. A second ultrasound, 1 week later, showed three distinct foci of cardiac motion in one sac, while the sac of the monoamniotic twins had one embryo with heart beat. After extensive counseling with perinatologists about pregnancy complications, the patient elected to performed fetal reduction on the third sac. A healthy male infant was delivered by Caesarean section at 38 weeks of gestation. CONCLUSIONS: The exact mechanism of monozygotic multiple gestation is still poorly characterized. Procedures that modify the zona pellucida (e.g. ICSI and assisted embryo hatching) have been suggested as important in the monozygotic multiple gestation hypothesis, yet a definitive relationship between any clinical intervention during in vitro fertilization and the subsequent development of multiple monozygotic gestation remains speculative.
