Temporal- and hormone-dependent changes in uterine sensitization for the decidual cell reaction and decidualization in vitro of rat endometrial stromal cells

The extracellular Ca 21 -sensing receptor (CaR) is a member of the superfamily of G protein-coupled receptors (GPCRs). It is an important mediator of a wide range of Ca 21 -dependent physiological responses in various tissues. In reproductive tissues it has been reported to play a significant role in promoting or maintaining placentation. Meanwhile, another Ca 21 regulated gene stanniocalcin-1 (STC-1) has been documented to be involved in decidualization and uterine remodelling. The phenomenon that CaR mediates STC-1's transcription responding to extracellular calcium in fish urges us to suppose that CaR, like STC-1, may also play a role in implantation and decidualization. To resolve this conjecture, we have examined the expression and hormonal regulation of the CaR gene in rat uterus during peri-implantation period. CaR mRNA was expressed at a moderate level in the luminal epithelium of the early stage of pregnancy (from day 1 to day 3). From day 2-3 it began to be expressed more strongly in the stromal cells immediately underneath the luminal epithelium, but decreased to a basal level on day 4. From day 6 to day 9 continuously, both CaR mRNA and protein were highly expressed in the primary decidua. Expression of CaR mRNA and protein in these cells was also observed when a delayed implantation was terminated by estrogen treatment to allow the embryo implantation. In contrast, only basal level expression of the molecules was detected in the cells of animals subjected to a normal-delayed implantation or the pseudopregnant condition. Embryo transplantation experiment confirmed that CaR expression at the implantation site was induced by the implanting blastocyst. Consistent with the normal pregnant process, CaR mRNA and protein in the cells were also induced by an artificial decidualization procedure. Further experiments demonstrated that treatment of the ovariectomized rat with estrogen or/and progesterone stimulated a high level expression of CaR mRNA in the uterine epithelial and glandular epithelium. In conclusion, CaR was specifically induced during the processes of implantation and subsequent decidualization and may play a role in these processes.Reproduction (2005) 129 779-788

“…Artificial decidualization was induced according to the procedures described by Kennedy and Ross (1997). The uteri were collected at 24 h, 48 h and 72 h after injection of the sesame oil.…”

Section: Artificial Decidualizationmentioning

confidence: 99%

Extracellular Ca2+-sensing receptor expression and hormonal regulation in rat uterus during the peri-implantation period

Xiao¹,

Yuan²,

Li³

et al. 2005

“…Mature female rats were ovariectomized and sensitized for the decidual cell reaction 5 days later according to the procedures described by Kennedy and Ross (1997). Some of the rats were given intrauterine injection of 100 ml sesame oil around noon on the equivalent of day 5 of pseudopregnancy.…”

Section: Animals and Treatmentsmentioning

confidence: 99%

Signal transducer and activator of transcription 3 (Stat3) expression and activation in rat uterus during early pregnancy

Teng

Diao²,

Ma³

et al. 2004

Signal transducer and activator of transcription 3 (Stat3), a member of the Stat family, is specifically activated during mouse embryo implantation. The aim of this study was to investigate the expression, activation and regulation of Stat3 in rat uterus during early pregnancy, pseudopregnancy, delayed implantation and artificial decidualization. Stat3 mRNA was highly expressed in the luminal epithelium on day 5 and in the luminal epithelium and underlying stromal cells at implantation sites on day 6 of pregnancy. There was a strong level of Stat3 protein expression and phosphorylation in the stromal cells near the lumen and in the luminal epithelium on day 5 of pregnancy, which was similar to day 5 of pseudopregnancy. In the afternoon of day 6, the strong level of Stat3 phosphorylation was detected only in the luminal epithelium. Stat3 was highly expressed and activated in the decidual cells from days 7 to 9 of pregnancy and under artificial decidualization in the present study. Our results suggest that the strong level of Stat3 activation in the luminal epithelium and underlying stromal cells during the preimplantation period may be important for establishing uterine receptivity as in mice, and the high level of Stat3 expression and activation in decidual cells may play a role during decidualization.

“…Animals were ovariectomized under isoflurane anesthesia (Abbot Laboratories, Saint-Laurent, QC, Canada) and allowed at least 5 days to recover. Ovariectomized rats were treated with oestradiol and progesterone s.c. to mimic pseudopregnancy as previously described (Kennedy & Ross 1997). To induce decidualization, animals received a bilateral injection of 0.1 ml sesame oil into the uterine lumen around noon on the equivalent of day 5 of pseudopregnancy and were referred to as stimulated as opposed to non-stimulated ( NS).…”

Section: Animal and Tissue Preparationmentioning

confidence: 99%

“…On the equivalent of day 5 of pseudopregnancy, the day of maximal uterine sensitization for the DCR (Kennedy & Ross 1997) the rats were randomized to the appropriate number of treatment groups for that experiment to receive unilateral intrauterine infusions of PGE 2 (Cayman Chemical Company) or various agonists. Because of differing solubility properties of the compounds, it was not possible to compare the effects of all of them in a single experiment.…”

Section: Intrauterine Infusionsmentioning

confidence: 99%

Expression patterns and role of prostaglandin-endoperoxide synthases, prostaglandin E synthases, prostacyclin synthase, prostacyclin receptor, peroxisome proliferator-activated receptor delta and retinoid x receptor alpha in rat endometrium during artificially-induced decidualization

Gillio-Meina¹,

Phang²,

Mather³

et al. 2009

To determine if changes in endometrial expression of the enzymes and receptors involved in prostaglandin (PG) synthesis and action might provide insights into the PGs involved in the initiation of decidualization, ovariectomized steroid-treated rats at the equivalent of day 5 of pseudopregnancy were given a deciduogenic stimulus and killed at various times up to 32 h thereafter. The expression of PG-endoperoxide synthases (PTGS1 and PTGS2), microsomal PGE synthases (PTGES and PTGES2), cytosolic PGE synthase (PTGES3), prostacyclin synthase (PTGIS), prostacyclin receptor, peroxisome proliferator-activated receptor d (PPARD) and retinoid x receptor a (RXRA) in endometrium was assessed by semiquantitative RT-PCR, western blot analyses and immunohistochemistry. In addition, to determine which PG is involved in mediating decidualization, we compared the ability of PGE 2 , stable analogues of PGI 2 , L165041 (an agonist of PPARD), and docasahexanoic acid (an agonist of RXRA) to increase endometrial vascular permeability (EVP, an early event in decidualization), and decidualization when infused into the uterine horns of rats sensitized for the decidual cell reaction (DCR). EVP was assessed by uterine concentrations of Evans blue 10 h after initiation of infusions. DCR was assessed by the uterine mass 5 days after the initiation of the infusions. Because enzymes associated with the synthesis of PGE 2 , including PTGS2, are up-regulated in response to a deciduogenic stimulus and because PGE 2 was more effective than the PGI 2 analogues and PPARD and RXRA agonists in increasing EVP and inducing decidualization, we suggest that PGE 2 is most likely the PG involved in the initiation of decidualization in the rat.