Expression Of UPA And UPAR Proteins On Bovine Cumulus-oocyte Complexes

The combine of urokinase plaminogen activator(uPA) and it receptor uPAR can activate multi-singal pathway in somatic cells, promote cell mitosis, inhibit cell apoptosis. But whether uPAR expression in bovine COCs or not and the significance of the uPA expression in bovine follicle has not been reported. In order to understand the co-expression of uPA and it specific receptor uPAR on bovine cumulus-oocyte complexes(COCs), we studied immaturate bovine cumulus oocyte complexes with immunohistochemistry and western blot which detect the expression of uPA and uPAR protein on bovien secondary follicle, cumulus cell and oocyte. The result of immunohistochemistry find uPA protein is expressed on cumulus cell, granula cell and theca cell but not on oocyte; uPAR protein is expressed on cumulus cell, granula cell, theca cell and oocyte. The result of Western blot shows the detection of 55 and 43kD specific protein band is comform to uPA and uPAR protein molecular weight. It not only proved the effectiveness of human source antibody on bovine cells, but also verification the result of immunohistochemistry on examination of protein of bovine cumulus cell and oocyte. Which means uPAR protein is expressed on bovine cumulus cell and oocyte. uPA protein is expressed on bovine oocyte. uPA can promote the formation of polocyte. The result imply uPA which is expressed by oocyte can function on the uPAR of bovine cumulus cell and oocyte by autocrine and paracrine pathway which has significant function on the process of bovine follicle development and oocyte maturation.