Development of a model system for the study of maternal recognition of pregnancy in the mare /
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| Other Authors: | , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1992.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | A model system was developed to analyze cellular interactions and signalling events between embryonic and maternal tissues involved in maternal recognition of pregnancy in the mare. This study employed an integrated analysis of the structural and functional properties of the endometrium and trophoblast cells during this period. Two strategies for isolating uterine epithelial cells from the mare were used including endometrial biopsies from nonpregnant and pregnant mares or enzymatic dissociation of cells from uterine tracts obtained at slaughter. Ultrastructural and histochemical analysis of tissue showed similarities in uterine morphology between early pregnancy and diestrus. Variations in levels of secretory activity were observed between the groups. Structural evidence for cell-to-cell communication via gap junctions was not widespread in the endometrial tissue, although small gap junctions were detected in the deep glandular epithelial cells. In order to evaluate the potential for the intercellular diffusion of regulatory and informational molecules between cells in contact, analysis of gap junction-mediated intercellular communication (GJIC) was conducted. For this analysis, a fluorescence recovery after photobleaching method was employed. Groups of contacting cells obtained from biopsies of mares in estrus, diestrus, and early pregnancy were capable of GJIC. Differences in GJIC between stages were not significant (P >.05) at the recovery times measured. A functional syncytium (with regard to ions and small molecules) may exist between equine endometrial epithelial cells under certain culture conditions. By contrast, monolayers of uterine epithelial cells isolated from uterine tracts showed negligible cell-to-cell communication. To examine maternal interactions with trophoblastic cells, trophoblastic vesicles were prepared by mechanical dissociation of Day 12 and 15 embryos after transcervical flushing. Cell-to-cell communication was detected between lipid-containing trophectoderm cells in monolayers. Structural and functional interactions occurring between equine endometrial cells, and between the blastocyst and endometrial cells, which are vital to the maintenance of pregnancy can be investigated using the described model systems. By understanding the temporal formation of a functional syncytium between endometrial cells, it may be possible to detect and identify critical signaling events associated with embryo recognition. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Physiology of Reproduction." |
| Physical Description: | xii, 121 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |