EN
Ovarian oxytocin (OT) and endometrial leukemia inhibitory factor (LIF) are involved in estrous cycle regulation and implantation of the blastocyst in cows. For this reason the authors investigated the effect of DDT and its metabolites (DDE), known as environmental pollutants, on the expression of genes involved in OT and LIF synthesis. Granulosa from follicles (1 cm in diameter), luteal and endometrial cells from cows on days 8-12 of the estrous cycle were treated for 6 h with DDT, p,p’-DDE, o,p’-DDE and technical mixture (MIX) of DDE isomers (10 ng/ml each). Obtained RNA was reverse transcribed and cDNA was amplified by PCR using primers for genes of NP-I/OT, PGA, LIF and G3PDH as a reference gene. DDT and DDE in granulosa cells and DDE in luteal cells increased (P < 0.05) the expression of the NP-I/OT gene, while DDE in granulosa cells and MIX in luteal cells increased the expression of the PGA gene (P < 0.05). In contrast, p,p’-DDE and MIX reduced (P < 0.05) the LIF expression in endometrial cells. Obtained data allow the authors to assume that DDE and its metabolite impairs regulation of the estrous cycle, affecting OT and LIF synthesis on the genomic level.