Abstract
Postnatal development of the Sertoli cell population was studied in testes taken from newborn mice and implanted into the testes of normal, hypophysectomized and testosterone‐treated hypophysectomized adult mice for 13, 15–17 and 17–19 days, respectively. Maturation of the Sertoli cell complement of each specimen was judged by two criteria: (1) the proportion of Sertoli cells exhibiting a nucleolonema; (2) the prevalence of specialized inter‐Sertoli cell junctions. In these respects implants recovered from normal hosts did not differ from sibling controls of the same age. Sertoli cells in implants recovered from hypophysectomized hosts retained the features observed in newborn controls, indicating that maturation of the Sertoli cells is dependent on normal pituitary function. Implants recovered from testosterone‐treated hypophysectomized hosts exhibited a degree of Sertoli cell development intermediate between those recovered from the other two host categories.