Uterine specific antigens in the ewe

Area of Science:

• Reproductive Biology
• Animal Science
• Biochemistry

Background:

• Uterine fluid composition changes throughout the estrous cycle and pregnancy.
• Identifying specific uterine proteins can provide insights into reproductive physiology.

Purpose of the Study:

• To analyze protein content in ewe uterine flushings during the estrous cycle.
• To identify and characterize uterine-specific antigens and their hormonal regulation.
• To investigate the impact of pregnancy on uterine protein synthesis and embryo development.

Main Methods:

• Analysis of total protein in uterine flushings at different cycle stages.
• Immunological detection of uterine-specific antigens using antisera.
• Hormonal manipulation (progesterone, estrogen) in ovariectomized ewes.
• In vitro studies of endometrial protein synthesis and embryo culture.

Main Results:

• Increased protein content in uterine flushings from days 9, 12, and 15 compared to earlier stages.
• Two uterine-specific antigens detected in flushings from days 7, 11, and 15 of the cycle, induced by progesterone or estrogen/progesterone.
• A third antigen found in kidney and endometrial extracts, present even in ovariectomized ewes.
• No pregnancy-specific antigens detected in uterine flushings during gestation.
• No significant differences in endometrial protein synthesis or embryo development in vitro.

Conclusions:

• Ewe uterine fluid protein concentration and specific antigen presence are influenced by the estrous cycle and hormones.
• Pregnancy does not appear to induce unique protein antigens in uterine flushings.
• Endometrial secretions do not significantly impact early embryo protein synthesis in vitro.