Vasectomy: Morphological and Immunological Effects in the Rat

McDonald, Stuart William (1989) Vasectomy: Morphological and Immunological Effects in the Rat. PhD thesis, University of Glasgow.

Abstract

This thesis examines morphological and immunological effects of vasectomy in inbred Albino Swiss rats. It comprises six separate studies. 1) The response of the regional testicular lvmoh node six and nine months after vasectomy. This work extends a previous study and shows that, while the response to vasectomy of the regional testicular lymph node increased in magnitude up to and including 3 months after operation, it waned through 6 and 9 months. The findings indicate the involvement of the regional lymphatics and lymph nodes in the formation of circulating antisperm antibodies after vasectomy. The response of the testicular nodes varied between individual rats. 2) The lymphatic drainage of the epididymis and of the ductus deferens, with reference to the immune response to vasectomy. The lymphatic drainage pattern of the unoperated reproductive tract is determined. Epididymal lymphatics always united with those of the testis. There is little previous work on lymphatics of the ductus deferens. The more cranial part of the scrotal ductus drained towards the inguinal canal and the iliac nodes. Lymphatics from the more caudal part of the ductus united with those of the epididymis. The results suggested a lymphatic watershed about the middle of the scrotal ductus. The role of variations in the lymphatic drainage of the sperm granuloma, the site of release of spermatozoal antigens, in the variable responses of the testicular lymph node to vasectomy is investigated. Vasectomy did not interrupt the lymphatic drainage of the epididymis. While lymph from epididymal granulomas invariably reached the regional testicular node that from vasal granulomas may occasionally have failed to do so. Variations in the lymphatic drainage of vasal granulomas, but not epididymal ones, may have been partly responsible for the lack of response in certain testicular nodes reported previously. 3) The response of the regional lymph node to epididymal sperm granulomas after vasectomy. The contribution of variations in the lymphatic drainage of vasal sperm granulomas to the variable nodal response to vasectomy is further analysed. By carrying out vasectomy at the junction of the ductus deferens with the epididymal duct, sperm granulomas were induced to form at the epididymis; at this site, their lymph always drains to the testicular node. In spite of the presence of epididymal granulomas in all rats 12 weeks after vasectomy, not all testicular nodes responded. It is concluded that variations in the lymphatic drainage of vasal granulomas had not been wholly responsible for the variations in the response of the testicular lymph node found previously and that additional unknown factors were involved. 4) On the mode of sperm autoantigen presentation to the regional lymph node of the testis after vasectomy. Cytological smears were used to detect whole spermatozoa in the testicular lymph nodes of vasectomised rats. Very few spermatozoa were found; this contrasts with the large numbers reported, by others, in nodes from rams and boars. The basis of this species difference is unclear. 5) A quantitative study of the effect of vasectomy on spermatogenesis. Quantitative studies of the cycle of the seminiferous epithelium and seminiferous tubular dimensions were performed on the testes of rats vasectomised for 6 months. The results indicate that, in functional tubules, there was no alteration in the cycle of the seminiferous epithelium, no tubular distension and no retention of spermatozoa. 6) The effect of testicular biopsy on the regional lymph node of the testis. Testicular biopsy, like vasectomy, damages epithelial barriers of the reproductive tract. This study investigates whether the procedure produces lymph node changes similar to those seen after vasectomy. The testicular lymph nodes of rats 1 and 3 months after testicular biopsy were indistinguishable in every way from those of sham-operated control animals. The absence of lymph node changes following testicular biopsy is likely to reflect the minimal amount of spermatozoal extravasation and inflammation in the testis. The study offers some reassurance about the safety of testicular biopsy in the investigation of male infertility.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Morphology, Immunology
• Date of Award: 1989
• Depositing User: Enlighten Team
• Unique ID: glathesis:1989-77799
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jan 2020 11:53
• Last Modified: 14 Jan 2020 11:53
• URI: https://theses.gla.ac.uk/id/eprint/77799