首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Evidence for a role of the ovarian surface epithelium in the ovulatory mechanism of the sheep: secretion of urokinase-type plasminogen activator
Institution:1. Department of Mathematics, Faculty of Science, Jiangsu University, 212013, China;2. Department of Basic Science, Obour High Institute for Engineering and Technology, Cairo 11828, Egypt;3. Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia;4. Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia;5. Department of Physics, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia;6. Department of Mathematics and Statistics, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;7. Department of Physics and Engineering Mathematics, Faculty of Electronic Engineering, Menoufia University, Menouf 32952, Egypt
Abstract:The extent of dissolution of tissues within the apical wall of the preovulatory ovine follicle (formative site of rupture) is greater than that of the counterpart basal hemisphere. It has been hypothesized that proteolytic enzymes released from contiguous ovarian surface epithelial cells contribute to apical follicular weakening and ovulation. Ovulation occurs from the dominant ovarian follicle of proestrous ewes at approximately 24 h after administration of luteinizing hormone-releasing hormone (LHRH). Follicular rupture was inhibited in sheep in which the ovarian surface epithelium was surgically removed at 8 (but not at 16) h following LHRH. Plasminogen activator bioactivity was greater within the follicular apex compared to basal wall at 12 h; this difference was negated by prior removal of epithelium at 8 h after LHRH. A low Mr plasminogen activator of the urokinase-type (uPA) was secreted by epithelial cells recovered from the surface of preovulatory follicles (Western blot analysis). Ovarian epithelium, not associated with a preovulatory follicle, produced very little uPA. Finally, ovulation was suppressed by intrafollicular injection (8 h post-LHRH) of uPA antibodies. It is suggested that secretion of uPA by ovarian surface epithelium and consequent plasmin up-regulation within neighboring tunica albuginea and follicular theca is a contributing factor in the mechanism of ovulation.
Keywords:
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号