الفهرس 
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Abstract
Introduction: The close morphological association between Sertoli cells and germ cells at different stages of their development (such as spermatogonia, spermatocytes, round spermatids, and elongated spermatids) is clearly visible in the seminiferous epithelium. As a result of such morphological intimacy between Sertoli and germ cells, it is conceivable that extensive interactions and communications take place between these cells throughout spermatogenesis both at the biochemical and molecular level. Spermatogenesis that occurs in the seminiferous epithelium of adult mammalian testes is associated with extensive junction restructuring at the Sertoli–Sertoli cell, Sertoli–germ cell, and Sertoli–basement membrane interface.While this morphological phenomenon is known and has been described in great details for decades, the biochemical and molecular changes as well as the mechanisms/signaling pathways that define changes at the cell– cell and cell–matrix interface remain largely unknown. We summarize thefindings in this field regarding the coordinated efforts of the anchoring [e.g., adherens junctions (AJs), such as basal ectoplasmic specialization (basal ES)] and tight junctions (TJs) that are present in the same microenvironment, such as at the blood–testis barrier (BTB), or at distinctly opposite ends of the Sertoli cell epithelium, such as between apical ectoplasmic specialization (apical ES) in the apical compartment, and the BTB adjacent to the basal compartment of the epithelium. These efforts, in turn, regulate and coordinate different cellular events that occur during the seminiferous epithelial cycle. Specialized junctions occur at sites of cell-cell and cell matrix contact in all tissues. They are the means by which cells communicate with each other and with their environment. Several decades of research have demonstrated that there are three morphologically and functionally distinct types of cell junctions present in epithelia. Some spermatogonial stem cells residing near the basement membrane transform into type B spermatogonia, which enter into the cell cycle by differentiating into preleptotene spermatocytes, traversing the blood–testis barrier (BTB) and migrate progressively across the seminiferous epithelium. However, germ cells remain attached to Sertoli cells for nourishment and structural supports at all time during the epithelial cycle while differentiating into spermatozoa. During this active cell migration process, intermittent junction disassembly and reassembly occur at the Sertoli–Sertoli cell and Sertoli– germ cell interface. If cross talk between these cells is disrupted, spermatogenic cells cannot migrate and/or orientate properly in the seminiferous epithelium. This leads to germ cell apoptosis, premature germ cell depletion from the epithelium, and infertility. Aim of work: demonstrate the physiology and biology of junction dynamics in the testis, and to put conclusion regarding this issue. Additionally; recommendations, conclusions and future directions will be presented. Conclusions: The use of a specific Rho-associated protein kinase (ROCK) inhibitor, Y-27632, could effectively block AF-2364-induced adherens junction disruption and the subsequent loss of germ cells from the epithelium and used in male contraception. Further studies are needed for complete evaluation of Sertoli-germ cell interactions and dynamics in The testis and its impact on male infertility.