Seminiferous Tubules

The human testicular parenchyma contains several important structures. Spermatozoa is produced in the germinal epithelium of the seminiferous tubules and released into the lumina of these ducts. The germinal lining contains both Sertoli cells and the developing spermatocytes. The interstitial space contains clumps of darker, eosinophilic cells. These are the Leydig cells, which produce and release testosterone. Myoid cells surround the tubules and generate rhythmic contractions to propel spermatozoa and fluid. They also synthesize collagen and other fibers of connective tissue.