Evidence for a Preimplantation Rise in Oestradiol-17  Levels on Day 4 of Pregnancy in the Mouse

McCormack, Janet; Greenwald, Gilbert S.

doi:10.1530/jrf.0.0410297

Cited by 104 publications

(62 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In mice, implantation depends on an ovarian estrogen surge that occurs during the morning of day 4 (11,12). To evaluate whether activation of Wnt͞␤-catenin signaling was regulated by estrogen, we removed both ovaries from pregnant transgenic females before the onset of the estrogen surge and administered animals with either progesterone alone or a mix of progesterone and estrogen.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Uterine Wnt/β-catenin signaling is required for implantation

Mohamed

Jonnaert

Labelle‐Dumais

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

210

161

View full text Add to dashboard Cite

Successful implantation relies on precisely orchestrated and reciprocal signaling between the implanting blastocyst and the receptive uterus. We have examined the role of the Wnt͞␤-catenin signaling pathway during the process of implantation and demonstrate that this pathway is activated during two distinct stages. Wnt͞␤-catenin signaling is first transiently activated in circular smooth muscle forming a banding pattern of activity within the uterus on early day 4. Subsequently, activation is restricted to the luminal epithelium at the prospective site of implantation. Activation at both sites requires the presence of the blastocyst. Furthermore, inhibition of Wnt͞␤-catenin signaling interferes with the process of implantation. Our results demonstrate that the Wnt͞␤-catenin signaling pathway plays a central role in coordinating uterus-embryo interactions required for implantation.blastocyst ͉ uterus A crucial event during mammalian embryonic development is the process of implantation, during which the free-living blastocyst attaches to the uterine endometrium. Successful implantation depends on precisely orchestrated and reciprocal signaling between the implanting blastocyst and the receptive uterus (1). For instance, blastocysts can only implant once they have been activated by uterine factor(s) that are regulated by ovarian steroid hormones (2). Conversely, expression of several uterine genes are regulated by a signal(s) emanating from activated blastocysts (3, 4). Multiple signaling pathways have been shown to participate in the implantation process, and several cytokines and growth factors have been shown to be expressed in the uterus at the time of implantation and to play important roles in this process (5). However, there is increasing evidence that members of other families of growth factors implicated in embryogenesis may also participate in the implantation process. It has been demonstrated that members of the hedgehog, bone morphogenetic, and Wnt proteins are expressed in the uterus at the time of implantation (6). However, the precise role of these different growth factor signaling pathways in the implantation process has not been determined. Furthermore, the cell types within the uterus that respond to these growth factors are not known. In this study, we set out to determine the role of the canonical Wnt͞␤-catenin signaling pathway in the implantation process. We demonstrate that this pathway is activated during two distinct stages before implantation. Signaling is transiently detected in circular smooth muscle forming a banding pattern of activity. Subsequently, activation is restricted to the luminal epithelium at the prospective site of implantation. Activation at both sites requires the presence of the blastocyst. Furthermore, we show that inhibition of Wnt͞␤-catenin signaling interferes with the process of implantation. Materials and MethodsMating and Experimental Manipulation of Transgenic Animals. The generation and characterization of the TCF͞Lef-LacZ transgenic mice have been described in ...

show abstract

Section: Resultsmentioning

confidence: 99%

“…2 H and I). Thus, estrogen injection, which is required to reactivate dormant blastocysts in utero and the resumption of implantation (11,12), is also required for blastocysts to trigger Wnt͞␤-catenin signaling in the uterine endometrium.…”

Section: Resultsmentioning

confidence: 99%

Uterine Wnt/β-catenin signaling is required for implantation

Mohamed

Jonnaert

Labelle‐Dumais

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

210

161

View full text Add to dashboard Cite

show abstract

“…Hence, an oestrogen surge is needed to initiate the endometrium receptivity period, during which implantation would be accepted [22][23]. The blastocyst itself most likely contributes to the hormonal mechanisms leading to its own implantation [24].…”

Section: Discussionmentioning

confidence: 99%

Oestrogen and progestogen receptors in endometrium and myometrium at the time of blastocyst implantation in pregnant diabetic rats

Hertogh¹,

Vanderheyden²,

Glorieux³

et al. 1989

Diabetologia

View full text Add to dashboard Cite

Summary.A suitable hormonal environment is a prerequisite for blastocyst implantation. Experimental diabetes was previously shown to modify the hormonal milieu and produce alterations in oestrogen receptor kinetics in the uterine tissue. In the present work, oestrogen and progestogen receptor levels were measured on the morning of day 6 of pregnancy in normal and in streptozotocin-induced diabetic rats, both in implantation sites and in interembryonic segments of endometrium and myometrium. Receptor levels were different in the implantation sites compared to the interembryonic segments of endometrium, both in the control and in the diabetic animals. Indeed, implantation sites were characterized by lower oestrogen receptor levels in cytosol and higher progestogen receptor levels in cytosol and nuclei. However, compared to the control rats, the diabetic rats had lower oestrogen receptor levels in implantation sites, both in cytosol and nuclei. In the myometrium, the differences between sites or between types of rats were minimal. Plasma levels of oestradiol were lower in diabetic rats than in control animals, whereas progesterone levels were similar. A 20% lower implantation rate was found in diabetic rats, compared to normal rats. These results show that the specific distribution of oestrogen and progestogen receptors between implantation sites and interembryonic segments was preserved in the diabetic rats; however the absolute level of oestrogen receptor was lower. This abnormal endocrine milieu might arise from a lower oestradiol level and a decreased oestradiol/progesterone ratio in the circulating blood. Whether the lower implantation rate in diabetic rats might be a consequence of the overall disturbed hormonal status remains to be elucidated.

show abstract

“…The proper balance of serum progesterone and oestradiol is necess¬ ary both for embryo transport and development (Roblero & Garavagno, 1979). Progesterone is necessary for the maintenance of pregnancy and, along with an oestradiol surge, for implantation (Deanesly, 1966;McCormack & Greenwald, 1974). As discussed previously, prolactin, ACTH and corticosteroids could all be involved in mediating these stress responses.…”

Section: Methodsmentioning

confidence: 98%

The effect of restraint stress in early pregnancy in mice

Wiebold¹,

Stanfield²,

Becker³

et al. 1986

Reproduction

View full text Add to dashboard Cite

Summary. Mice were exposed to 5 h of restraint stress on Days 1\p=n-\3,4\p=n-\6, or 1\p=n-\6of pregnancy in the morning (08:30\p=n-\13:30h, a.m.) or afternoon (13:30\p=n-\18:30h, p.m.). Stress reduced the pregnancy rate from 90 to 52% (P < 0\m=.\005) and average litter size on Day 18 from 8\m=.\2to 5\m=.\2 young (P < 0\m=.\005). Stress for 6 days was more effective than for 3 days (P < 0\m=.\005) and an a.m. stress was more effective than a p.m. stress (P <0\m=.\05)

show abstract

Evidence for a Preimplantation Rise in Oestradiol-17 Levels on Day 4 of Pregnancy in the Mouse

Cited by 104 publications

References 10 publications

Uterine Wnt/β-catenin signaling is required for implantation

Uterine Wnt/β-catenin signaling is required for implantation

Oestrogen and progestogen receptors in endometrium and myometrium at the time of blastocyst implantation in pregnant diabetic rats

The effect of restraint stress in early pregnancy in mice

Contact Info

Product

Resources

About