The blood-testis barrier is a selective interface within the seminiferous tubule, formed principally by junctions between neighboring Sertoli cells. Its tight junctions restrict the extracellular route toward developing germ cells, helping maintain a specialized environment for spermatogenesis. Despite its name, the key junctional seal is between supporting epithelial cells, rather than simply between blood vessel walls and the rest of the testis.[ref]
Anatomy and Physiology 2e by J. Gordon Betts and others. Section27.1: Sertoli-cell organization and blood-testis barrier
A 1999 experiment tested a molecular component. Mice lacking the membrane protein Claudin-11 were male-sterile, and freeze-fracture electron microscopy showed absence of the normal tight junction strands between their Sertoli cells. The conjunction of a defined genetic alteration, an altered junctional structure and impaired reproduction provides stronger evidence than identifying a dark line in one section.[ref]
CNS myelin and Sertoli cell tight junction strands are absent in Osp/claudin-11 null mice by A. Gow and others. Abstract: null mice, freeze-fracture strands and reproductive deficit
Selective separation does not mean complete isolation. Supporting cells still exchange substances through controlled cellular routes. A useful tracer experiment would compare whether a probe can pass between Sertoli cells under matched conditions; its distribution would test access for that probe, not prove that every solute crosses identically.
Articles by others on the same topic
There are currently no matching articles.