HA4: Testis - H & E
There are three important supporting cell types in the testis (HA4). Sertoli cells (S) are inside the tubules and they function as supportive cells. Sertoli cell nuclei are large, oval and euchromatic, usually oriented perpendicular to the basement membrane. Although it is difficult to see in light micrographs, Sertoli cells surround the spermatogenic cells similar to how Schwann cells cradle unmyelinated axons. Myoid cells (arrows) are just outside the seminiferous tubules. They contract to help move the immotile sperm and fluid out of the seminiferous tubules. Interstitial cells of Leydig (LC) are another cell type found between the tubules. These cells have a foamy looking cytoplasm that is typical of steroid secreting cells (Cell Biology HA11). They synthesize testosterone, which stimulates spermatogenesis.