ABSTRACT
Considering the importance of integrin molecules in the implantation and lack of sufficient information in the expression pattern of these molecules in various phases of estrous cycle. It seemed to be necessary to investigate these molecules in mouse endometrial during the various phases of oestrous cycle. Female NMRI mice [n=15] aged 6-8 weeks were studied. Various phases of estrous cycle including: proestrus, estrus, metestrus and diestrus were determined by vaginal smear. The mice were sacrificed [at least 3 per each phase] by cervical dislocation and the tissues were obtained from the middle 1/3 part of their uterine horns at each phase then the cryosections at thicknesses between 8-10 micro were obtained. Then the immunohistochemistry were done for integrins of alpha4, beta1, alphav, beta3 and their ligand osteopontine. The integrins were expressed only in the metestrous phase of oestrous cycle in the different locations of mouse endometrium. The positive reactions were observed for alphav, alpha4 and beta3 in the apical and basal membrane of glandular epithelium. Also the positive reaction for beta1 was found in surface and glandular epithelium as well as stroma. The osteopontin expression was seen in the apical membranes of surface and glandular epithelium and was not seen in other locations. It seems that expression of integrins in endometrium is based on their role in the implantation, therefore the molecules alpha4, beta1 and OPN that are expressed on the surface epithelial may be involve in the adhesion of cell to cell and integrins of alphav, beta3 that are expressed in the glandular