CONICET | Buscador de Institutos y Recursos Humanos

Introduction: During the last years it has become clear that lipid molecules are active mediators of embryo invasion and that they play pivotal roles in immune regulation. Knock out mice in LPA3, one of lysophosphatidic acid (LPA) receptors, present severe deficiencies in implantation. LPA modulates prostaglandins (PGs) production in bovine, pig and ovine uteri. PGs and anandamide are described as crucial mediators of embryo invasion. PGE2 and PGI2 promote neovascularization and decidualization in rodent uteri. High anandamide levels correlate with aberrant implantation and blastocyst apoptosis. Thus, the aim of our work was to study the effect of LPA on relevant mediators of implantation in the rat. Materials and methods: Day 5 pregnant rat uteri were incubated with LPA 50µM for 6h. PGE2 production was assessed by radioimmunoassay and mRNA and protein expression by RT-PCR and western blot. Significance was determined using t-Student. Results: The expression of LPA3 mRNA and protein in the rat uterus was modulated during early gestation. The incubation with LPA augmented FAAH expression (p<0.05), the enzyme that degrades AEA. LPA treatment also increased COX-2 expression (p<0.05) and PGE2 synthesis (2,1±0,1 vs 2,7±0,2 pgPGE2/mg ww, p<0.05) . Finally, LPA was capable to induce the expression of IGFBP-1, a molecular marker of decidualization. Conclusion: LPA is a potent lipid mediator that seemed to favor embryo implantation.