Role of conceptus secretory products in establishment of pregnancy.
Abstract: Conceptuses produce steroids, prostaglandins, proteins and possibly other unidentified agents which may play a role in the establishment and maintenance of pregnancy. A key event in this process is protection of the corpus luteum (CL) from the luteolytic activity of prostaglandin (PG) F-2 alpha of uterine origin. Oestrogens produced by the pig conceptuses between Days 11 and 16 appear to exert an antiluteolytic effect resulting in the sequestering of PGF-2 alpha within the uterine lumen. Failure of the pregnant uterus to release PGF-2 alpha in an endocrine fashion, therefore, allows for maintenance of CL function. Conceptuses of sheep and cattle produce proteins which, when introduced into the uterine lumen of nonpregnant ewes and cows, suppress the ability of oestradiol and oxytocin to stimulate uterine production of PGF-2 alpha. These conceptus secretory proteins appear to exert an antiluteolytic effect by inhibiting uterine production of luteolytic amounts of PGF-2 alpha. The horse conceptus produces both oestrogens and proteins during early pregnancy when uterine production of PGF-2 alpha is suppressed. Co-culture of horse endometrium and conceptus inhibits endometrial production of PGF-2 alpha. Conceptuses of pigs, sheep and cattle undergo elongation to achieve apposition between trophectoderm and endometrium but the horse embryo migrates rapidly and consistently throughout the uterus to achieve endometrial contact.
Publication Date: 1986-03-01 PubMed ID: 3517318DOI: 10.1530/jrf.0.0760841Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
- Research Support
- U.S. Gov't
- Non-P.H.S.
- Research Support
- U.S. Gov't
- P.H.S.
- Review
Summary
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The research investigates the role of various substances secreted by conceptus (the embryo in the stage of early development) in establishing and maintaining pregnancy, with emphasis on how these substances protect the corpus luteum (a temporary endocrine structure in mammals after ovulation).
Conceptus secretory products and their roles
- Conceptus secretions include steroids, prostaglandins, proteins, and other yet unidentified substances that may support pregnancy establishment and maintenance.
- Prostaglandin F-2 alpha, a compound of uterine origin, has luteolytic activity which means it can lead to the regression of the corpus luteum. Conceptus-produced substances shield the corpus luteum from this luteolytic compound.
Oestrogens and the antiluteolytic effect
- Oestrogens, which are produced by the pig conceptus between days 11 and 16 of pregnancy, exhibit an antiluteolytic effect, meaning they protect the corpus luteum from regression.
- These oestrogens cause the sequestration of PGF-2 alpha within the uterine lumen, in effect preventing its release in an endocrine manner which helps maintain the functionality of the corpus luteum.
Conceptus secretory proteins in sheep and cattle
- In sheep and cattle, their conceptus produce proteins that, when transferred into the uterine lumen of nonpregnant ewes and cows, inhibit the ability of estradiol and oxytocin to stimulate the production of PGF-2 alpha in the uterus.
- These proteins function to exert an antiluteolytic effect by suppressing the uterine production of luteolytic quantities of PGF-2 alpha.
Horse conceptus and its production
- In horse pregnancies, both oestrogens and proteins are produced during the early phase when the production of PGF-2 alpha by the uterus is being inhibited.
- When the endometrium of the horse is co-cultured with a conceptus, the production PGF-2 alpha is suppressed. This indicates that the conceptus-produced substances play a similar antiluteolytic role as in other species.
Comparison of different conceptus
- In pigs, sheep, and cattle, the elongation of the conceptus is needed to allow contact between the trophectoderm (the layer of cells forming the outer shell of a very early stage embryo) and the endometrium (the inner lining of the uterus).
- However, in horses, the embryo moves quickly and consistently throughout the uterus to establish contact with the endometrium.
Cite This Article
APA
Bazer FW, Vallet JL, Roberts RM, Sharp DC, Thatcher WW.
(1986).
Role of conceptus secretory products in establishment of pregnancy.
J Reprod Fertil, 76(2), 841-850.
https://doi.org/10.1530/jrf.0.0760841 Publication
Researcher Affiliations
MeSH Terms
- Animals
- Blastocyst / physiology
- Cattle / physiology
- Corpus Luteum / physiology
- Dinoprost
- Embryo Implantation
- Estradiol / physiology
- Estrogens / physiology
- Female
- Horses / physiology
- Oxytocin / physiology
- Pregnancy
- Pregnancy, Animal
- Prostaglandins F / physiology
- Proteins / physiology
- Sheep / physiology
- Swine / physiology
- Uterus / physiology
Grant Funding
- HD10436 / NICHD NIH HHS
Citations
This article has been cited 15 times.- Bigler NA, Gross JJ, Baumrucker CR, Bruckmaier RM. Endocrine changes during the peripartal period related to colostrogenesis in mammalian species. J Anim Sci 2023 Jan 3;101.
- Huidrom LD, Dhanaji SN, Pandey S, Chandra V, Gutulla TS. Embryo-Uterine Cross-Talk: Exploration of the Immunomodulatory Mechanism in Buffalo. Animals (Basel) 2022 Nov 14;12(22).
- Tan C, Huang Z, Xiong W, Ye H, Deng J, Yin Y. A review of the amino acid metabolism in placental function response to fetal loss and low birth weight in pigs. J Anim Sci Biotechnol 2022 Mar 2;13(1):28.
- Fiorenza MF, Amaral CDS, da Anunciação ARA, Portela VVM, Marey MA, Miyamoto A, Antoniazzi AQ. Possible impact of neutrophils on immune responses during early pregnancy in ruminants. Anim Reprod 2021;18(3):e20210048.
- Amaral CDS, Correa GRE, Serrano Mujica LK, Fiorenza MF, Rosa SG, Nogueira CW, Portela VM, Comim FV, Schoenau W, Smirnova NP, Antoniazzi AQ. Heat stress modulates polymorphonuclear cell response in early pregnancy cows: I. interferon pathway and oxidative stress. PLoS One 2021;16(9):e0257418.
- Köse AM, Sarıbay MK, Koldaş Ürer E, Naseer Z, Doğruer G, Karaca F, Coşkun Çetin N. Estimation of periostin as a biomarker for early pregnancy diagnosis in goats: a preliminary study. Iran J Vet Res 2021 Winter;22(1):72-75.
- Camacho CA, Estradé MJ, Cazales N, Caballeros JE, Fiala-Rechsteiner SM, Neves AP, Mattos RC. Histomorphometric and vascular changes in equine endometrium after the infusion of conceptus fragments. Anim Reprod 2020 Jun 29;17(2):e20200006.
- Huang J, Liu R, Su L, Xiao Q, Yu M. Transcriptome Analysis Revealed the Embryo-Induced Gene Expression Patterns in the Endometrium from Meishan and Yorkshire Pigs. Int J Mol Sci 2015 Sep 18;16(9):22692-710.
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