Abstract: In the mammalian testis，tight junction is the primary structure of the blood-testis barrier （BTB） between adjacent Sertoli cells. This structure coexists with the basal ectoplasmic specializations and desmosome-gap junctions. Physically，the BTB divides the seminiferous epithelium into two distinct compartments：a basal compartment where spermatogonia and early spermatocytes are found，and an adluminal compartment where more developing germ cells existed in. In order to enter the adluminal compartment，preleptotene spermatocytes must pass through the BTB，in which several molecules and signalling pathways participate. In this review，we summarized some research results concerning the effect of relevant cellular junctions and junctional proteins of BTB on the penetration of preleptotene spermatocytes.

Key words: Blood-testis barrier, Sertoli cells, Tight junctions, Connexins, Spermatogenesis