It is generally agreed that the testis is under endocrine control from the pituitary, and is influenced by physiological and paracrine factors within the organ.The aim of this study is to analyze the effect of unilateral and bilateral epididectomy on the testicular tissue growth of rats.Twenty- one male old Sprague-Dawley rats (28 days old) were used in the study. Rats were assigned into 3 equal groups. The first group was the control group, while unilateral and bilateral epididectomy was performed on the second and third groups, respectively. Twenty-one days after the epididectomy, testicular tissues from each group were taken and fixed in Bouin solution. Paraffin sections were stained with Haematoxylin and Eosin, Vangiesson, PAS-Hemalun and examined by light microscopy.Disorganization of the germinal epithelium, desquamation, degeneration and edema in interstitial tissue was seen in the testicular cross sections of the unilateral group. Arrest in spermatozoon stage in some tubules and presence of eosinophylic stained multinucler bodies were recognizable. In the bilateral group, degeneration and atrophic status in the seminiferous tubules of the bilateral group was observed preciesly, and occasional interstitial edema and perforations in the basal lamina were recognizable. In addition, vasodilatation, arrest in spermatozoa stage and multinucleated bodies in some of the seminiferous tubules lumen were observed in some testicular cross sections of this group.As a result, epididectomy causes degeneration in the germinal epithelium and hypoplasia in Leydig cells.It is concluded that epididectomy causes degeneration in the germinal epithelium, interruption of spermatogenesis, and a notable decrease in the number of Leydig cells
