Prostaglandins and sex steroids from corpora lutea of pregnant mares. In vitro studies.

The research investigates hormone function and potential differences in one and three-month pregnant horse ovaries, focusing on a few hormones and how certain treatments affect their production. The study suggests that certain biological processes are likely controlled by different hormones at different stages.

Prostaglandins and Sex Steroids in Pregnant Mares

In this study, scientists are trying to understand the functioning of certain hormones in pregnant mares, namely, Prostaglandin F (PGF), Prostaglandin E2 (PGE2), Progesterone, and 17 beta-estradiol. The corpus luteum, the term used to describe parts of the ovaries, from pregnant horses at one-month and three-month stages were compared to study any functional difference.

• The quantities of PGF, PGE2, and 17 beta-estradiol were found to be significantly higher in the corpora lutea of one-month pregnant mares compared to three-month ones.
• Progesterone production, however, was almost equal in both one-month and three-month corpus luteum.

Effects of Treatments on Hormone Production

The in vitro effects of different hormones were also observed on the synthesis of prostaglandins and sex steroids.

• On administering PGE2 treatment, the 17 beta-estradiol levels decreased in one-month corpora lutea.
• With progesterone treatment, PGE2 levels increased in both one-month and three-month corpora lutea.
• 17 beta-estradiol treatment resulted in an increase in PGE2 levels in one-month corpora lutea.

Conclusions of the Study

The chief observation of this study is that hormone control over certain biological processes seems to be stage-dependent. Specifically, it is proposed that PGE2 production in one-month corpora lutea could be regulated by both progesterone and 17 beta-estradiol, while in three-month corpora lutea, the regulation seems to be under the control of only progesterone. This research provides valuable insights into the complex hormonal regulation of pregnancy in mares and will be useful for future studies in the field of reproductive biology in large animals.