j cumhuriyet univ health sci inst Instıtute of Health Sciences Journal 2587-0874 Sivas Cumhuriyet University Veterinary Sciences (Other) Veteriner Bilimleri (Diğer) Embryonic Testis Development, Anatomy and the Role of Spermatogonial Stem Cells in Spermatogenesis https://orcid.org/0000-0001-6271-6088 Ağır Vahit SELCUK UNIVERSITY https://orcid.org/0000-0002-2955-8599 Bucak Mustafa Numan 08 30 2025 10 2 169 187 07 25 2025 08 14 2025 Copyright © 2016, Instıtute of Health Sciences Journal 2016 Instıtute of Health Sciences Journal

Spermatogenesis is a highly coordinated process that ensures the continuous production of spermatozoa in adult males. This process originates from spermatogonial stem cells (SSCs) located in the basal compartment of the seminiferous tubules. SSCs are unique among adult stem cells in that they not only maintain the stem cell pool through self-renewal but also give rise to differentiated germ cells that contribute genetically to the next generation. Spermatogenesis involves sequential stages of proliferation, meiosis, and morphological maturation, supported by Sertoli cells and regulated by endocrine signals from the hypothalamic pituitary gonadal axis.In this context, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play essential roles by acting on Sertoli and Leydig cells, respectively, to sustain the microenvironment required for germ cell development. Leydig cell-derived testosterone exerts its effects through classical and non-classical pathways, modulating gene expression and cellular interactions critical for spermatogenesis. Furthermore, spermatozoa undergo functional maturation during epididymal transit, acquiring motility and fertilizing capacity.Understanding the biology of SSCs and the molecular and hormonal mechanisms controlling spermatogenesis has profound implications for reproductive medicine, infertility treatment, and the conservation of endangered species. Recent advances in SSC isolation, culture, and transplantation have highlighted their potential in both regenerative and reproductive applications, although significant challenges remain in maintaining their viability and purity during manipulation.

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