Focal Changes in the Seminiferous Tubules of Vasectomized Hamsters

The hamster testis was studied by light and electron microscopy at intervals of two weeks, five months, and one year after vasectomy. No changes were detected at two weeks, but most testes showed microscopic alterations at subsequent intervals. The most striking characteristic of the lesions was their patchy distribution, in which severly altered profiles lay next to apparently normal seminiferous tubules. A spectrum of changes was present, characterized by varying degrees of depletion of germ cells. There were numerous vacuoles in the cytoplasm of Sertoli cells and dilatations of the extracellular space between adjacent Sertoli cells. Both spaces frequently were surrounded by a layer of cytoplasm that resembled that of Sertoli junctional specializations. One testis prepared a year after vasectomy contained multiple infiltrates of phagocytic cells. Possible mechanisms of focal testicular damage after vasectomy are considered.