We shall study some of the biochemical interactions which occur between the preimplantation blastocyst and the endometrium which allow for the establishment of pregnancy. We plan to purify two early products of the sheep conceptus. One of these (Proteir X), a low molecular weight protein, is released, during a restricted period of development during which maternal recognition of pregnancy occurs. It can be purified from the medium after culturing whole conceptuses in vitro using ion-exchange and gel filtration chromatography. The protein is taken up by the uterine epithelium where specific membrane receptors appear to exist. We shall investigate whether introduction of Protein X into the uterine lumen of Day 12-14 non-pregnant ewes leads to maintenance of corpus luteum function or induction of a state of pseudopregnancy. We plan to measure effects on endometrial protein synthesis, particularly on the production of secreted proteins, in a quantitative manner and determine whether it influences the pattern of endometrial steroid or prostaglanding metabolism. Finally, we shall test whether the protein is mitogenic. The second sheep blastocyst product is a large glycoprotein. We propose to detect its site of synthesis and deposition by immunocytochemical techniques and determine whether it is immunosuppressive towards sheep lymphocytes by means of in vitro tests. In a second area of study, we plan to study whether spherical pig blastocysts are able to elongate and develop normally in vitro when cultured in reconstituted uterine secretions. Such studies will allow us to investigate the mechanism of cellular reorganization and understand the role of maternal secretory products in blastocyst development. A final project is to study whether the progesterone-induced protease inhibitors secreted by the uterine endometrium control blastocyst invasiveness. This will be achieved by transferring Day 12 blastocysts to uteri not producing inhibitor to determine whether they can then invade. We shall also measure whether blastocysts can degrade components of the extracellular matrix of cultured cells. These experiments may define some of the parameters which control trophoblast inevasiveness.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD010436-12
Application #
3311293
Study Section
Reproductive Biology Study Section (REB)
Project Start
1977-03-01
Project End
1990-12-31
Budget Start
1989-07-01
Budget End
1990-12-31
Support Year
12
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Florida
Department
Type
Schools of Medicine
DUNS #
073130411
City
Gainesville
State
FL
Country
United States
Zip Code
32611
Mirando, M A; Harney, J P; Zhou, Y et al. (1993) Changes in progesterone and oestrogen receptor mRNA and protein and oxytocin receptors in endometrium of ewes after intrauterine injection of ovine trophoblast interferon. J Mol Endocrinol 10:185-92
Bazer, F W; Mirando, M A; Ott, T L et al. (1992) Roles of ovine trophoblast protein-1 and oestradiol/prolactin in the establishment of pregnancy in sheep and pigs. Reprod Fertil Dev 4:335-40
Ott, T L; Mirando, M A; Davis, M A et al. (1992) Effects of ovine conceptus secretory proteins and progesterone on oxytocin-stimulated endometrial production of prostaglandin and turnover of inositol phosphate in ovariectomized ewes. J Reprod Fertil 95:19-29
Bazer, F W; Johnson, H M (1991) Type I conceptus interferons: maternal recognition of pregnancy signals and potential therapeutic agents. Am J Reprod Immunol 26:19-22
Ko, Y; Lee, C Y; Ott, T L et al. (1991) Insulin-like growth factors in sheep uterine fluids: concentrations and relationship to ovine trophoblast protein-1 production during early pregnancy. Biol Reprod 45:135-42
Bazer, F W; Thatcher, W W; Hansen, P J et al. (1991) Physiological mechanisms of pregnancy recognition in ruminants. J Reprod Fertil Suppl 43:39-47
McDowell, K J; Sharp, D C; Fazleabas, A T et al. (1990) Two-dimensional polyacrylamide gel electrophoresis of proteins synthesized and released by conceptuses and endometria from pony mares. J Reprod Fertil 89:107-15
Buhi, W C; Alvarez, I M; Sudhipong, V et al. (1990) Identification and characterization of de novo-synthesized porcine oviductal secretory proteins. Biol Reprod 43:929-38
Mirando, M A; Ott, T L; Harney, J P et al. (1990) Ovine trophoblast protein-one inhibits development of endometrial responsiveness to oxytocin in ewes. Biol Reprod 43:1070-8
Pontzer, C H; Ott, T L; Bazer, F W et al. (1990) Localization of an antiviral site on the pregnancy recognition hormone, ovine trophoblast protein 1. Proc Natl Acad Sci U S A 87:5945-9

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