Organ
Seminiferous tubules
Coiled epithelial tubes where sperm develop
High-yield
Junctions between Sertoli cells divide the epithelium into basal and adluminal compartments. Spermatogonia occupy the basal side, so the blood-testis barrier does not enclose every germ cell behind one immune boundary.
Overview
Within each testicular lobule, coiled seminiferous tubules contain germ cells at successive stages of sperm formation. Sertoli cells span the epithelium and support this process, while contractile myoid cells surround the tubules. Straight terminal segments connect the tubules to the rete testis; Leydig cells occupy the intervening tissue.
Reference facts
- Location
- They fill the lobules bounded by testicular connective-tissue septa, with interstitial tissue between neighboring tubules.
- Parts
- A coiled sperm-producing segment leads to a short straight tubule. Germ cells and Sertoli cells rest on a basal lamina surrounded by peritubular myoid cells.
- Blood supply
- Capillary networks supplied by intratesticular arterial branches lie outside the tubular epithelium; exchange with developing cells occurs across supporting tissue and cellular barriers.
- Innervation
- Testicular autonomic fibers accompany the regional vessels. Germ-cell development is regulated chiefly through hormonal and local cellular signals.
- Function
- The tubules produce sperm. Sertoli cells provide support and barrier functions and release inhibin B; anti-Müllerian hormone is especially important in fetal and immature Sertoli-cell function.
Clinical correlation
Barrier disruption can contribute to antisperm immune responses, but local immune regulation also protects the testis. Klinefelter syndrome commonly causes progressive germ-cell loss and fibrotic seminiferous tubules. Leydig cells may become hyperplastic even when testosterone production is impaired.
Frequently asked questions
Where are the seminiferous tubules located?
They fill the lobules bounded by testicular connective-tissue septa, with interstitial tissue between neighboring tubules.
What do the seminiferous tubules do?
The tubules produce sperm. Sertoli cells provide support and barrier functions and release inhibin B; anti-Müllerian hormone is especially important in fetal and immature Sertoli-cell function.
What are the parts of the seminiferous tubules?
A coiled sperm-producing segment leads to a short straight tubule. Germ cells and Sertoli cells rest on a basal lamina surrounded by peritubular myoid cells.
What is the blood supply of the seminiferous tubules?
Capillary networks supplied by intratesticular arterial branches lie outside the tubular epithelium; exchange with developing cells occurs across supporting tissue and cellular barriers.