Regulatory role of prostaglandin E2 in establishment and maintenance of pregnancy in cattle: Molecular and cellular interactions

In ruminants, recognition, establishment and maintenance of pregnancy involve several molecular and cellular interactions between the conceptus, uterus, and corpus luteum (CL). PGF2alpha is the luteolysin and also a myometrial stimulant while PGE2 is considered as luteoprotective mediator and a myometrial relaxant. Embryonic interferon tau is the pregnancy recognition signal. We have studied the prostaglandin (PG) biosynthetic, transporting and signaling systems in uterus and CL. Our results have shown that PGE 2 and PGF2alpha biosynthetic enzymes, transporter and receptors are expressed in a tissue specific and spatio-temporal manner in endometrium, myometrium and CL during the estrous cycle and pregnancy. PGE2 biosynthesis and signaling is preferentially activated during recognition and establishment of pregnancy. Collectively, our results suggest an important and selective role for PGE2 and PGF2alpha in uterus and corpus luteum function in cattle. Treatments targeting PGE2 and PGF2alpha biosynthetic enzymes, transporter and receptor could constitute the basis for the development of new therapeutic strategies to regulate fertility.