Endocrine and Paracrine Regulation of Mammalian Spermatogenesis

Publisher Summary Spermatogenesis is composed of the mitotic divisions of spermatogonia to produce spermatocytes, the two meiotic divisions, and the differentiation of the resulting spermatids to spermatozoa. The mammalian testis is composed of the seminiferous tubular and interstitial compartments. Within the seminiferous epithelium are the somatic Sertoli cells and the developing germ cells with which the Sertoli cells are associated. Spermatogenesis proceeds in an ordered fashion that includes diploid spermatogonial stem cells dividing mitotically to become spermatocytes, the two meiotic divisions producing haploid round spermatids, and the differentiation of the spermatids to elongated, mature sperm. In addition to their ability to differentiate, a subset of the spermatogonial cells are able to self-renew, thereby maintaining a pool of stem spermatogonia required for the continuous production of male gametes.