The Regulation And Expression Of Cellular Prion Protein In Mice Implantation And Decidualization Of The Uterus

OBJECTIVE:In this study, Kunming mice were used as experimental materials, by constructing mice early pregnancy, artificial decidualization, steroid hormone treatment, delayed implantation and delayed implantation activation as animal models. The regulation and expression pattern of cellular prion protein (PrPc) were studied by Real-time PCR, in situ hybridization and immunohistochemistry. This study was designed to explore the possible mechanism of PrPc in mice implantation and decidualization of the uterus, and lay the foundation to reveal the normal physiological function of PrPc.METHODS:(1)Constructing mice early pregnancy, artificial decidualization, steroid hormone treatment, delayed implantation and delayed implantation activation as animal models;(2) The expression of PrPc mRNA of mice uterus in early pregnancy, steroid hormone treatment and artificial decidualization animal models was detected by Real-time PCR;(3) The expression of PrPc mRNA of mice uterus in early pregnancy, steroid hormone treatment and artificial decidualization animal models was detected by in situ hybridization;(4) The expression of PrPc of mice uterus in early pregnancy, artificial decidualization delayed implantation and delayed implantation activation animal models was detected by immunohistochemistry.RESULTS:(1) In uterus of early pregnancy mice, Real-time PCR results showed that the expression of PrPc mRNA level of day8of pregnancy was significantly higher than that in day5of pregnancy; the PrPc mRNA was mainly detected in the sub-luminal stroma surrounding implanting blastocyst and decidua cells by in situ hybridization, and expression of PrPc mRNA gradually increased in the decidua from days7to8of pregnancy. The expression of PrPc protein was mainly detected in the sub-luminal stroma surrounding implanting blastocyst and decidua cells from day5of pregnancy. The expression was mainly located at the decidua since day6of pregnancy. Expression of PrPc was gradually increased in the decidua from days7to8of pregnancy. During delayed implantation activation, the expression of PrPc was mainly detected in the sub-luminal stroma surrounding implanting blastocyst and decidua cells which was much alike to day5of pregnancy, but yet, signal was slightly detected in the delayed implantation.(2)During artificial decidualization, all the results suggested the expression of PrPc mRNA, PrPc was detected strongly in the decidua undergoing artificial decidualization. In contrast, there was only a weak signal in the luminal and glandular epithelium of control uterus horn.(3)During steroid hormone treatment mice models the PrPc mRNA expression level was declined, however, the difference was not statistically significant, which indicated the PrPc may not under the regulation of progesterone.CONCLUSION:(1) The expression level of PrPc mRNA and protein increased with the increase of the degree of decidualization, thus we speculated that PrPc participate the decidualization and may be involved in maintenance of pregnancy.(2)The PrPc protein was specifically expressed in implantation site suggested that it may involve in embryo implantation.(3) The PrPc mRNA expression level was declined after progesterone treatment either in vitro or in vivo, however, the difference was not statistically significant, which indicated the PrPc may not under the regulation of progesterone.