Abstract

PIP: Rats underwent either left unilateral or bilateral vasectomy; the vas deferens was ligated at both ends and a piece of it was removed. 1 animal was sacrificed each week at 1-8 months. Zones I-VI of the epididymis, as described by Reid and Cleland (1957), were studied from both the vasectomized and contralateral sides. When the vasectomized side was compared with the contralateral unoperated side or with controls, no consistent difference was seen in the diameters of the ducts from the various regions of the epididymis (caput, corpus, cauda, and vas). Findings in Zones I-VI are summarized. The vasectomized side had an accumulation of lysosomes and residual bodies in the principal cells; this indicated resorption of spermatozoa. On the contralateral side similar accumulations were seen after 10 weeks. Spermatozoa seem to be first broken down and only then resorbed by the epithelial cells of the epididymal duct. Luminal breakdown of spermatozoa may be due to aging of spermatozoa or a reduced production of certain secretory products by the epididymis. A third possibility, secretion of a lytic substance by the epididymis, is made somewhat untenable by a lack of substantial increase in acid phosphatase levels in the epididymis.