Morphological Studies of the Immune Response to Vasectomy

• Main Author: Al-Saffar, Raith A. S
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-1987
• Subjects: Immunology; Medicine; Morphology
• ISBN: 0438507290; 9780438507296

1. The morphological changes in the epididymis, testes, and spleen, were studied at seven postoperative periods (6 wks and 4, 6, 9, 12, 15, and 18 mos.) after unilateral (left) vasectomy or sham operation, in a series of 72 mature Albino rats. 2. In a group of 6 additional animals, in which vasectomy was performed on the left side, with the right vas as a sham-operated control, the luminal surface of the epididymis was studied by scanning electron microscopy, at 1, 3 and 6 wks after operation. 3. Spermatic granulomas developed first at the site of vasectomy. They gradually increased in size, and in many of the rats, particularly at longer intervals after vasectomy, granulomas appeared in the epididymis, usually initially in the cauda, followed by their appearance in the corpus and caput. In such animals, the vasal granulomas became reduced in size. 4. Epididymis: (a) in all but 3 rats, there was no distension of the epididymal duct, no thinning of the epithelium and no histological and EM changes in the epithelium. In the remaining 3 animals, all of which had a granuloma in the caput, the duct was distended with sperm and the epithelium was thinned. (b) no evidence was found of the uptake of sperm or sperm fragments by the epididymal epithelium. (c) Intraepithelial leucocytes in both sham-operated and vasectomized animals were identified by EM as lymphocytes, monocytes and macrophages. (d) The numbers of intraepithelial leucocytes did not differ significantly between sham-operated and vasectomized animals at any of the time intervals after operation. (e) A site of microscopic rupture of the epididymal duct and the early formation of a granuloma has been studied in a longitudinally sectioned epididymis. The histological appearances suggest the following sequence of events: i. obstruction of flow of sperm and fluid along the duct; ii. distension of the duct, with thinning and weakening of its epithelial wall; iii. the escape of sperm into the stroma; iv. the development of a granulomatous inflammatory reaction; v. invasion of the duct lumen by polymorphonuclear leucocytes and macrophages. (f) Lymphatics: In the vicinity of a granuloma these contained a variable number of lymphocytes and macrophages. These cells were not seen in sham-operated animals or in vasectomized animals at a site remote from a granuloma. (g) SEM appearances: No differences were seen in the surface morphology of the epididymal epithelium of sham-operated and vasectomized animals. 5. The Testes remained histologically normal up to four months after vasectomy. However in the period between 6 to 18 months after operation, 11 rats showed patchy degenerative changes of seminiferous tubules in their left testes. This was attributed to the development of a granuloma in the caput epididymidis which caused an obstruction and led to an increase in the intraductal hydrostatic pressure. Four animals at the same period, showed bilateral testicular atrophy. No evidence was found to suggest a cause, such as infection, immunological orchitis, ischemia, or cryptorchidism. The cause remained unclear. 6. Spleen: The spleen showed no evidence of involvement in an immune response to vasectomy, as assessed by the absence of significant changes in each of the following parameters: weight volume density of white pulp volume density of marginal zone germinal centres.