Uterine and placental expression of HPGD in cows during pregnancy and release of fetal membranes

- The expression of 15-hydroxyprostaglandin dehydrogenase (HPGD) in bovine uterus and placenta is time-dependent.
- Bovine placental HPGD is localized in uninucleated trophoblast cells.
- HPGD-expression seems to be progesterone-dependent and does not differ between retained and released bovine placenta.
- HPGD seems to be involved in establishment and termination of gestation in cattle by regulating local bioavailability of prostaglandins.

15-Hydroxyprostaglandin dehydrogenase (HPGD) plays a key role in prostaglandins (PGs) catabolism. Its expression and activity appear to be regulated by progesterone (P4). We investigated the HPGD mRNA-expression and protein localization in placentomes and interplacental uterine sites throughout gestation (Study I), and after fetal membranes retention (RFM) compared with normally delivered fetal membranes (DFM) (Study II). Furthermore, we analyzed the influence of aglepristone (AP), dexamethasone (GC) or cloprostenol (CP), on HPGD expression in bovine placentomes (Study III). Tissues from late gestation (D272) and at normal term (NT) served as controls. HPGD was highest in all sites at the beginning of pregnancy and at (NT). Following induced parturition HPGD was lower after (AP) and (GC) compared with (NT), and was similar in RFM and DFM. Placentomes stained primarily in fetal compartments; interplacentomal signals were observed in endometrial glandular and luminal epithelium. Results indicate that HPGD may play a role during establishment and termination of gestation.