PROFILE OF PROSTAGLANDIN-F2-ALPHA AND PROGESTERONE DURING PSEUDOPREGNANCY IN THE MOUSE

In rodents, luteal growth function and regression depend upon complex interrelationships between ovary, pituitary and uterus during the oest rous cycle and pregnancy when embryo signals prevent the demise of the corpus lutea (CL). The aim of the present work was to study the role of ovarian prostaglandin F-2alpha (PGF(2 alpha)) in the luteolysis of the mouse using a pseudopregnancy (psp) model. We measured by radioimm unoassays both PGF(2 alpha) and the release of serum progesterone as i ndicators of a functional corpus luteum. The production of uterine and ovarian PGF(2 alpha) was significantly greater at the beginning of th e luteolysis, on the 7th, 8th and 9th days in the uterus and on the 8t h day in the ovary. This suggests that both sources of PGF(2 alpha) ar e involved in the demise of the corpus luteum and in the end of pseudo pregnancy in the mouse.