Changes In Endometrial Receptivity In Mice Based On Different Conditions

Objective:To compare the endometrial expression of integrin beta3 and the level of endometrial interleukin-2,6 (IL-2,6),during the implanta- tion window in mice under five designed different conditions. To inve- stigate the influences on endometrial receptivity in mice of ovulation drugs , semen ,seminal plasma ,embryos and pregnant hormones and so on.Methods:The female mice were divided into two groups :pregnant group and pseudopregnant group. The pregnant group consisted of unilateral tubal ligation group(containing pregnant side and unpregnant side); the pseudopregnant group consisted of natural cycle group ,inducing ovulation group ,bilateral tubal ligation group.The two uterine specimens of these groups were taken respectively during day 2-7 of pregnancy were preserved in -80℃icebox.One went through immunohistochemistry stain to determine integrin beta3,the other was measured by enzyme-linked immunosorbant assay (ELISA) to determine the levels of IL-2,6.Results: 1.Integrin beta3: Integrin beta3 located in intracytoplasm of endometrial glandular epithelial cells and lunminal epithelial cells in mice during implantation window.On day 6 of pregnancy in the inducing ovulation group showed obvious signs ;On day 4 of other groups showed obvious signs. On day 4 to 5 of pregnancy compared with the pseudop- regnant group the integrin beta3 level in the pregnant group was signify- cantly higher (P<0.05); there were no differences between the natural cycle group and the bilateral tubal ligation group(P>0.05); there were no differ- rences between the two sides of the unilateral tubal ligation group (P>0.05).2.Interleukin-2: IL-2 regularly expressed in endometrium of mice during implantation window.On day 5 of pregnancy in the inducing ovula- tion group, the level of IL-2 decreased obviously;on day 4 in other groups it deceased obviously. On day 3 to 4 of pregnancy, the level of IL-2 in the pregnant group decreased more significantly than the pseudopregnant group (P<0.05);On day 3 to 4 of pregnancy, the level of IL-2 in the natural cycle group was lower than the inducing ovulation group (P<0.05) and in the bilateral tubal ligation group was lower than the inducing ovulation group too (P<0.05);there were no differences between the natural cycle group and the bilateral tubal ligation group(P>0.05); there were no differences between the two sides of unilateral tubal ligation group(P>0.05).3.Interleukin-6: IL-6 regularly expressed in endometrium of mice during implantation window.On day 5 of pregnancy in inducing ovulation group, the level of IL-6 increased obviously;on day 4 in other groups it increased obviously. On day 3 to 6 of pregnancy,the level of IL-6 in the pregnant group was higher than the pseudopregnant group (P<0.05); On day 4 to 5 of pregnancy,the natural cycle group increased more significantly than the bilateral tubal ligation group (P<0.05); the inducing ovulation group showed lower than other groups(P<0.05); there were no significant differences between the two sides of the unilateral tubal ligation group (P>0.05).4.The expression of IL-2 and IL-6 in endometrium of mice during implantation window showed negative correlation(r=-0.78,P=0.001).Conclusions:1.Integrin beta3 specially located in intracytoplasm of endometrial glandular epithelial cells and lunminal epithelial cells in mice during implantation window.It can be the endometrial receptivity marker.It maybe promote establishment of endometrial receptivity. 2.Interleukin-2 and-6 regularly reached peak value in endometrium of mice during implantation window,showed negative correlation ,depressed each other. They participated in the establishment of endometrial receptivity ,but it would wait for further research. 3.Compared with the natural cycle ,using PMSG and hCG to induce ovulation could decrease endometrial receptivity and delay the implantation window to open. 4.Seminal plasma could have positive regulations. Embryos influence the receptivity through indirect effect of excreted factors .