Endometrium Morphology Analysis And Expressions Of Galectin-3 And Integrin α4 In Mouse Endometrium During Early Implantation

Objective①To observe the histological changes of the endometrium of unpregnant (estrous stage) and pregnant mice during early implantation.②To analyze the expressions and distributions of Galectin-3 and Integrinα4 in the endometrium of pregnant mice during early implantation.③To explore the association between the expressions of Galectin-3 and Integrinα4 in the endometrium of pregnant mice during early implantation. Methods Adult nulliparity Kunming mice were taken as study objects. Three adult female mice were caged with a normal male overnight. In the following morning, females were checked for the presence of a vaginal sperm plug. The day of vaginal plug was regarded as day 1 of pregnancy. 50 pregnant mice were randomly divided into 5 groups and every group comprised 10 mice. Mice were executed by luxatioing cervical vertebra and got their uterus by paunching on day 1,2,3 ,4 and 5 of pregnancy. Meanwhile, we got uteri from ten unpregnant mice (estrous stage) taken as controls. The uteri were fixed in 4% paraformaldehyde for the following treatment respectively:①Hematoxylin-Eosin (HE) staining was used to observe histologic structures in endometrium;②Immunohistochemical SP staining was used to measure the expression of Galectin-3 and integrinα4 in mice endometrium;③The photoes about the expression were taken by microscopic imaging system and then the results of HE and immunohistochemical staining were analysed by computer. Results①The HE staining results: The unpregnant (estrous stage) mice endometrium were make up of luminal epithelium and lamina propria. In lamina propria, it contained uterine glands, stroma cells, blood vessels and so on. Uterine gland is single tubular glands. The types of luminal epithelium and glandular epithelium were both simple columnar epithelium. On day 1～5 of pregnancy, structure changes of mouse endometrium appeared developmental tendency. It showed that endometrium was thickening, hyperplasial and physiological edema, amounts of uterine glands increased gradually, intercellular space of stroma cells became augmented, and blood vessels accrementited.②The immunohistochemical staining results showed: In the glands epithelium, cavity and matrix cells of the unpregnant (estrous stage) and pregnant mice endometrium on day 1～5 exist the expression of Galectin-3.On day 1～5 of pregnancy, Galectin-3 were expressed Strengthen gradually in endometrium mice on day 1～2 of pregnant and were mainly distributed in the endometrial glandular epithelium and luminal epithelium. From day 3 of pregnancy, Galectin-3 were expressed enhanced obviously. On day 4～5 of pregnancy is strong expression. On day 3～5 of pregnancy, Galectin-3 had positive expression in stroma cells and expressed the most obviously on day 4 and 5. In the glands epithelium, cavity and matrix cells of the unpregnant (estrous stage) and pregnant mice endometrium on day 1～5 exist the expression of Integrinα4.On day 1～5 of pregnancy, Integrinα4 had weak positive expression in endometrium mice on day 1～3 of pregnancy and mainly expressed in luminal epithelium and glandular epithelium of uterus. Matrix cells almost don't express. On day 4～5 of pregnancy, Integrinα4 had strong positive expression in endometrium mice and mainly expressed in luminal epithelium , glandular epithelium and stroma cells of uterus.③The mean optical densities (MOD) of Galectin-3 and Integrinα4 in pregnant mice on day 1～5 were calculated through image analysis. The data by SPSS software indicated that there was a positive correlation between the expressin of Galectin-3 and Integrinα4 in pregnant mice endometrium on day 1～5. Conclusions①The morphological changes in the endometrium of pregnant mice on day 1～5 exhibted a dynamic changing tendency and the prominent changes appeared during the window of implantation.②The continued expression of Galectin-3 in the glands epithelium, cavity and matrix cells in the endometrial of pregnant mice on day 1～5 and expressed strongest on day 4～5. It suggested that Galectin-3 might play an important role in the process of the embryo implantation in mice.③The continued expression of Integrinα4 in the glands epithelium, cavity and matrix cells in the endometrial of pregnant mice on day 1～5 and expressed strongest on day 4～5. It suggested that Integrinα4 may take part in the process of mice embryo implantation.④The expressions of Galectin-3 and Integrinα4 have a positive correlation in the endometrium of pregnant mice on day 1～5 which suggested that Galectin-3 and Integrinα4 probably collaboratively were involved in the process of implantation.