The Expression Of β₃ Integrin Subunit And Fibronectin In The Human Fallopian Tube And Early Embryos

Objective: The present research was undertaken to explore the expression and distribution of PS integrin subunit, fibronectin, oestrogen receptor(ER) and progesterone receptor(PR) in normal human oviductal tissue during various phases of the menstrual cycle, and to study the morphological features of human oviductal epithelium during the menstrual cycle. We compared these results with the outcome of human tubal pregnancy. All these will result in our better understanding of the oviductal function and the etiology of tubal ectopic pregnancy.The distribution of fibronectin in human oocyte and 2-cell to morulae embryos was also investigated, and the possible roles of fibronectin in fertilization, the development of early embryo and implantation were also discussed.Materials and Methods: Normal and pregnant and inflammatory fallopian tube were collected from women who had normal menstrual cycle and had history of normal pregnancy. Normal fallopian tubes were divided into four groups based on their menstrual cycly. The expression and distribution of p3 integrin subunit, fibronectin, ER and PR in normal human oviductal tissue during the menstrual cycle and tubal pregnancy were investigated by using the immunohistochemical method and the image analysis. Indirect immunofluorescence was used to observe the distribution of fibronectin in human oocyte and 2-cell to morulaeembryos. The morphological features of the fallopian tube was studied by light microscopy. Results:1. The pa integrin subunit was expressed in the plasm of ciliated cells. The expression levelof Pa integrin subunit was highter after ovulation than before ovulation in isthmus epithelium (P < 0.001), and declined significantly after ovulation in ampullae epithelium (P < 0.001), and increased in umbrella epithelium in the four days after ovulation which was highter significantly than in other periods (P < 0.001) .2. No expression of the Pa integrin subunit was found in the epithelium of salpingitis.3. The ciliated and secretory cells of the epithelium except where the pregnancy occurred in tubal pregnancy expressed the p3 integrin subunit, and no significant relationship was found between the secretory normal and pregnant fallopian tube (P > 0.05) .4. Fibronectin was distributed in human oocyte and the inner cells of early embryos, and no difference was found. None was found in zona pellucida.5. ER and PR were expressed in the nucleus of epithelial cell of the endosalpinx during different phases of menstrual cycle and reached the peak before and after ovulation. No difference was found in the expression level of PR between the ciliated and secretory cells (P > 0.05). The expression level of ER was higher significantly in the secretory cells than in the ciliated cells (P < 0.01) .6. No correlation was found between the expression of the p3 integrin subunit and the ER, also the PR (P>0.05) .7. The expression level of PR was highter significantly in the epithelium except where the pregnancy occurred in tubal pregnancy than the human secretory normal oviduct (P < 0.001) . There was no difference in the expression level of ER in between these two groups (P>0.05) .8. The epithelium of the oviduct consists of ciliated and secretory cells chiefly. In the short time before and after ovulation, there was a richly ciliated epithelium and more secretory products than other time in menstrual cycle. Salpingitis induced the decrease of cilia. There was more secretory cells and less ciliated cells in tubal pregnancy compared with the nomal oviduct.Conclusion: These data suggested that the abnormal relaxation of smooth muscle and the the decrease of cilia wound result in the settling of embryo, and the epithelium of the endosalpinx and the matrix of the oviduct was receptive to the embryo at that time. The expression of the p3 integrin subunit in the umbrella epithelium may play an important role in oocyte pick up, and the expression of the p3 integrin subunit in the isthmus epithelium would be associated with the formation of...