Expression of COX-1 and COX-2 in the endometrium of cyclic, pregnant and in a model of pseudopregnant rats and their regulation by sex steroids.

Background: Cyclooxygenases (COXs) are the rate limiting enzymes in the process of prostaglandins (PGs) synthesis, which are critical regulators of a number of reproductive processes, including ovulation, implantation, decidualization and parturition. The aim of the present study was to investigate the expression and regulation of COX-1 and COX-2 and levels of prostaglandins during rat pregnancy, in a model of pseudopregnancy and estrous cycle.

Methods: Uteri were collected from the cyclic rats on each day of estrous cycle, after every two days for pregnant (days 2 to 22) and pseudopregnant rats (days 1 to 9).

Regulation of prostaglandin D synthase and prostacyclin synthase in the endometrium of cyclic, pregnant, and pseudopregnant rats and their regulation by sex steroids.

Prostaglandins (PGs) are critical regulators of a number of reproductive processes. To date, the presence and regulation of PGS in the rat endometrium have not yet been described. The objective of the present study was to investigate the expression of PGD synthase (PGDS) and prostacyclin synthase (PGIS) in the endometrium.