Degeneration of the seminiferous epithelium following epididymal obstruction in prepubertal rats.

The development of the testes was studied in rats following prepubertal obstruction of the epididymis. Male rats received bilateral ligation of the corpus epididymidis or a sham operation at 10 days of age, and temporal changes in testicular morphology and weights of reproductive organs were determined at intervals spanning sexual maturation. Development of the testes was normal through 35 days of age. The initial histological changes in the testes of ligated animals, observed at 56 days, included an increased diameter of the seminiferous tubule lumen, depletion of spermatids, and the presence of multinucleate spermatids. Subsequently, germ cells were greatly depleted in the testes of 91- and 128-day-old rats with ligated epididymides. After puberty, testicular weight and volume declined relative to corresponding sham-operated animals. On the other hand, the weights of the epididymides in ligated animals prior to puberty significantly exceeded those of sham-operated rats but weighed significantly less than those of rats in the sham group after sexual maturation. Testicular alterations occurred after increases in the weights of the epididymides. Testicular changes may have contributed to rather than resulted from an autoimmune response to spermatozoa because testicular alterations preceded increases in antisperm autoantibodies.