Evidence From Sertoli Cell-Depleted Rats Indicates That Spermatid Number in Adults Depends on Numbers of Sertoli Cells Produced During Perinatal Development*

To probe the relationship between the size of the Sertoli cell population, established during perinatal development, and production of germ cells in the adult testis, a Sertoli cell-depleted rat model was developed. This was accomplished by delivering an antimitotic drug, cytosine arabinoside (araC), directly to the testis of newborn pups. Initial studies of these araC-treated neonates indicated that 1) the drug is cleared rapidly from the testis; 2) it substantially reduces the level of Sertoli cell proliferation; 3) Sertoli cell division ceases at a normal time in spite of the previous drug treatment; and 4) araC itself has no residual effect on germ cell proliferation, which begins several days after the injection. Pups given araC were allowed to reach maturity, and their testes were perfuse-fixed for light microscopic morphometry. When the numbers of Sertoli cells in adult rats given araC as were compared with those in normal littermates, a 54% decrease in the size of the Sertoli cell population was d...