Ultrastructural changes in the rabbit epididymis following vasectomy and clip occlusion.

Adult male rabbits were subjected to vasectomy, tantalum clip occlusion and sham operations. Caput and cauda regions of epididymis were studied with electron microscope at intervals of 15 days and 15 months after operation. Vasectomized and clip occluded subjects revealed similar changes when compared with sham operated animals. The epithelium remained functionally active even after vasectomy and clip occlusion as indicated by the presence of all characteristic complements of cellular organelles. Increased number of vacuoles and electron dense bodies indicated enhanced absorptive and digestive mechanisms at 15 months of vasectomy and clip occlusion. Disposal of continuously producing spermatozoa following vas occlusion may take place by intraluminal disintegration of sperm and subsequent phagocytosis by epididymal epithelium as evidenced by presence of identifiable parts of spermatozoa and flocculent material in caput and cauda regions.