Role of Urokinase-type Plasminogen Activator in the Precontact Sperm-egg Communication and Fertility of Mice in vitro

作     者：Xiao-fang DING Cheng-liang XIONG Hong-gang LI yong-hong TIAN Jin-wen XIONG Lian HU 

作者机构：Center of Reproductive Medicine Tongji Medical College Huazhong University of Science and Technologe Wuhan 430030 China 

出 版 物：《Journal of Reproduction and Contraception》 (生殖与避孕（英文版）)

年 卷 期：2005年第16卷第4期

页      面：201-212页

学科分类：0710[理学-生物学] 07[理学] 071008[理学-发育生物学] 

基　　金：This work is supported by a grant of the National "Tenth Five Years" Key Technologies R&D Programme China(No.2004BA720A33-01) 

主　　题：urokinase-type plasminogen activator sperm chemotaxis precontact sperm-egg communication fertility 

摘      要：Objective To explore the role of urokinase-type plasminogen activator（uPA） in precontact sperm-egg communication and fertility of mice in vitro. Methods Firstly, sperm chemotaxis （SC） induced by uPA was assayed by measuring the sperm densities in capillaries with a descending gradient or no gradient of uPA respectively. Secondly, the role of uPAR that exists in sperm plasma membrane in SC was studied by examining the change of sperm density in capillary after incubating spermatozoa with anti-uPAR antibody. Thirdly, SC induced by eggs, which had been treated with uPA, PAl-1 and anti-uPAR beforehand respectively, was assayed to study the role of uPA in PSEC. Lastly, the fertilization capability of spermatozoa treated with uPA was examined by counting the number of fertilized eggs. Results 1）The density of spermatozoa that migrated down the gradient of uPA into the capillary was significantly lower than that into the capillary containing no-gradient uPA. 2） When uPAR of spermatozoa was inhibited by anti-uPAR antibody, the density of spermatozoa that migrated into the capillary with ascending gradient of uPA decreased correspondingly. 3） The density of spermatozoa attracted by eggs, which were treated with uPA beforehand, increased significantly than that of attracted by non-treated eggs. On the contrary, the sperm density decreased correspondingly when the egg was treated with PAI-1. 4） The number of fertilized eggs increased significantly after the spermatozoa used here was treated with uPA beforehand. Conclusion uPA could induce SC of mice sperm in vitro through the uPAR on its membrane, enhance the capability of egg inducing SC, and promote spermatozoa to fertilize eggs. Thus, uPA may act as an attractant in PSEC, increase the chance encounter of spermatozoa and eggs, therefore, enhance the fertility success correspondingly. This study, in some degree, provides an evidence that uPA may be used as a new medicine and diagnostic reagent for male infertility.