Effects of DDT, DDE, aldrin and dieldrin on prostaglandin, oxytocin and steroid hormone release from smooth chorion explants of cattle.

Chlorooganic xenobiotics (XBs) such as DDT, DDE, aldrin and dieldrin interfere with release of hormones from chorionic villi that are necessary for sustaining the normal course pregnancy: prostaglandins (PGs), oxytocin (OT), progesterone (P) and estradiol (E). Approximately 20 %-40 % of these hormones originate from the smooth chorion. The aim of current studies was to investigate effects of these XBs on synthesis and release of PGE, PGF, OT, P and E from explants of smooth chorion of cattle, obtained during the120-150 and 151-180 day gestational period. Explants were incubated with DDT, DDE, aldrin or dieldrin at concentrations of 1 and 10 ng/mL for 24 h, and concentrations of PGE, PGF, OT, P and E in post incubation medium and the relative abundances of COX-2, PTGES, AKR1B1, NP-I/OT, PAM, HSD3B, and CYP19A1 mRNA transcripts in tissue explants were determined. The XBs did not have effects on cell viability in explants (P > 0.05), however, there were effects on prostaglandins, OT and P secretion and relative abundance of mRNA transcript for genes encoding the main enzymes involved in synthesis of these hormones (P < 0.05). The XBs that were evaluated did not have effects on E synthesis and secretion (P > 0.05). In summary, XBs evaluated in the present study had effects on the pattern of prostaglandin secretion, and can increase OT and P release from smooth chorion explants. Because XBs inhibit hormonal action throughout the chorion, there is an increase in risk of abortions or premature births in animals.