Morphological, Histological, and Ultrastructural Changes in Epididymis after a Vasectomy

Abstract

The long-term effect of a vasectomy was investigated in this work. Twenty sexually mature New Zealand white male rabbits (Oryctolagus cuniculus) of proven fertility were used. The maturity of these rabbits was determined by the age of about 14 months from birth, palpation of genitalia, and examination of semen samples. The animals were divided into four groups: four rabbits were used as controls, and sixteen rabbits were vasectomized. After six months after vasectomy, we start taking a sample by exposing each group in one month after the previous one. The operated ducts revealed an increase in size in 7-8 months after vasectomy. The initial and terminal segments appeared greatly swollen and distended with fluid, resulting in the whole epididymis's increasing weight. Histological changes included a drop in the height of the lining epithelium and microvilli of the epididymis. After eight months of vasectomy, dilatation in the epididymal tubules increased its diameters, especially in the terminal segment. This caused an increase in the thickness of intertubular connective tissue. In addition, there was distension due to the intratubular pressure increase. This resulted in the tubular wall rupture and extravasation of spermatozoa into the interstitial tissue after 6-7 months from vasectomy. Eight months later, the epithelial lining was returned. The examination of morphological changes due to vasectomy was also investigated.