Effects Of Autonomic Nerves In Rat’s Uterus On The Expression Of β-catenin And Wnt-1during Embryo Implantation

Reproduction is a complex physiological process, participated by nerve, endocrine and immune system. Embryo implantation plays a major role in a successful pregnancy progress. During window period of the implantation, the embryo sac completes the implantation process via attachment, adhesion, penetration and trophoblast invasion. It depends in the complicated effects of neurotransmitters, endocrine hormones, cytokines and immune cells. Wnt signaling pathway is indispensable for implantation as a kind of cell signal transducing system. However, there are little evidences proving the autonomic nervous impacts on Wnt pathway during implantation. P-catenin and Wnt-1are the key molecules of Wnt pathway.The autonomic nerves innerving the rat uterus were removed by the surgery and chemical methods to observe status of embryo implantation, to detect the distribution of β-catenin and Wnt-1in the rat uterus on4d,5d and6d post pregnant using immunohistochemical method, and to analyze their different expressions by real time fluorescence quantitative RT-PCR technology. The results suggest,(1) Cavitation and nuclear pyknosis phenomena with different degree were observed in uterine glandular epithelium after nerve damage on5d-6d post pregnancy, and implantation delay occurred on5d post pregnancy.(2)β-catenin is mainly located in stromal cytoplasm, Wnt-1mainly is in stromal cytoplasm, glandular epithelium cytoplasm, membranes and luminal epithelium. The distribution and quantity of β-catenin and Wnt-1vary with different pregnancy stages. In normal, the expressions of p-catenin and Wnt-1in stromal cells are increased on4d, and decreased on5d, then increased on6d again. After damaging both sympathetic nerve and parasympathetic nerves, the expressions of β-catenin and Wnt-1are increasing with pregnancy days, and higher than that of normal group. After damaging sympathetic nerve, the expressions of P-catenin and Wnt-1were increased dramatically in stromal cells with pregnancy age, but significantly lower than those of normal group. After removal of parasympathetic nerve, β-catenin and Wnt-1expressions are more abundant than those of normal group on5d. These results indicate that abnormal expression of β-catenin and Wnt-1caused by neuroectomy may destroy the normal intrauterine microenviroment of embryo implantation, and result in implantation delay or lower implantation rate. Our relative quantitative determination results detected by real time PCR also confirm the same change trends.In summary, functional inhibition of autonomic nerves in uterus can influence the expression of β-catenin and Wnt-1, which result into embryo implantation delay in rats.