|
|
|
Testis: Seminiferous Tubules and Interstitium
|
- Seminiferous tubules are highly convoluted tubules lined by stratified epithelium that contain two distinct populations of cells:
- Spermatogenic cells: germ cells in various stages of maturation (70-day process)
(spermatogonia - primary spermatocytes - secondary spermatocytes- spermatids - spermatozoa)
- Sertoli cells: essentially the "nurse" cells that support and nourish the germ cells
non-dividing columnar cells located on the basement membrane, form tight junctions that compose the testis-blood barrier; and produce Müllerian inhibiting factor in embryogenesis.
- The interstitium between seminiferous tubules contain the Leydig cells (shown on right) which produce testosterone. These cells have round nuclei with 1-2 prominent nucleoli and abundant bright pink (eosinophilic) cytoplasm; the cytoplasm may contain lipofuscin pigment (golden-yellow) or cytoplasmic granules known as the crystals of Reinke (center of picture on right).
|
|
![](Javascript:PopUp('imagepopup.cfm?imagenumber=hist15.jpg&detail=Testis: Seminiferous Tubules and Interstitium: When assessing a "normal" testis, try to appreciate the presence of mature spermatids in the adluminal compartment (i.e., clustered towards the center of the tubular lumen). If you can identify those "arrow-head" cells, most likely the testicular biopsy is normal.'))
![](Javascript:PopUp('imagepopup.cfm?imagenumber=hist16.jpg&detail=Testis: Seminiferous Tubules and Interstitium: When assessing a "normal" testis, try to appreciate the presence of mature spermatids in the adluminal compartment (i.e., clustered towards the center of the tubular lumen). If you can identify those "arrow-head" cells, most likely the testicular biopsy is normal.'))