Expression And Regulation Of EP2 Gene In Rat Uterus During Early Pregnancy

Prostaglandin ? is important for implantation and decidualization. The aim of this study was to examine the expression and regulation of EP2 gene in rat uterus during early pregnancy, and under delayed implantation and artificial decidualization by in situ hybridization and immunohistochemistry.In rat uterus, no specific signals for EP2 mRNA were detected on days 1-4 of pregnancy. Weaker signals were first detected in the luminal epithelium on day 5. On day 6, strong signals for EP2 mRNA were detected in the luminal epithelium. EP2 mRNA signal was also detected in the luminal epithelium on days 7-8. However, no specific signals for EP2 mRNA were detected in decidua and embryo on days 6-9. EP2 immunostaining was gradually strengthened in the luminal epithelium and glandular epithelium from day 1 to 5 of pregnancy, followed by the gradual reducing of immunostaining on days 6-9. No specific signals for EP2 mRNA were detected in the uterus under delayed implantation, but strong signals were present in the luminal epithelium after reinitiation of implantation. In contrast, EP2 immunostaining was strong in the luminal epithelium and glandular epithelium under delayed implantation and reinitiation of implantation. Expression of EP2 mRNA and protein was not detected in the decidualized uterus, while EP2 immunostaining was seen in the luminal epithelium and glandular epithelium of control uterus horn. In conclusion, these results suggested that EP2 expression may play a role during implantation rahter than during decidualization.Postgraduate: Shi Jian-JunMajor: Animal Histology and EmbryologySupervisor: Professor Yang Zeng-Ming...