Inflammatory Changes in the Epididymis After Vasectomy in the Lewis Rat1

Abstract

The epididymides of Lewis rats were studied at intervals up to 7 months after vasectomy, vasectomy followed 3 months later by vasovasostomy, or sham operations. Epididymal histology was related to testicular alterations and to serum antisperm antibodies as determined with an enzyme-linked immunosorbent assay. In vasectomy and vasovasostomy groups. 13 of 33 rats had testicular alterations, which consisted mainly of pronounced depletion of germ cells. Over half of the rats with testicular alterations also had severe epididymal lesions that included interstitial changes characteristic of an inflammatory response. These consisted of aggregates of mononuclear cells, including lymphocytes, plasma cells, and macrophages. The lumina of epididymides with interstitial changes contained polymorphonuclear leukocytes and/or macrophages. All animals with altered testes had greatly decreased numbers of epididymal sperm. In many instances, the lumen of the proximal cauda epididymidis was collapsed, and columnar cells of the epididymal epithelium contained many very large lysosomes. The distal cauda epididymidis was distended with sperm and debris. None of the rats that lacked testicular alterations showed epididymal changes. Mean serum antisperm antibody levels were significantly higher for rats with epididymal interstitial changes than for animals without such epididymal alterations. Infiltrations of inflammatory cells into the epididymal interstitium and lumen are part of the constellation of changes that occurs after immunization with testicular homogenates to produce experimental allergic orchitis. The observations reported here support the hypothesis that reproductive tract alterations after vasectomy in this model have an immune basis.

Lipopolysaccharide-Induced Epididymitis Disrupts Epididymal Beta-Defensin Expression and Inhibits Sperm Motility in Rats1

“…The caput epididymis treated with LPS showed enhanced expression of Il1b and characteristics of inflammation, including hyperemia, interstitial edema, and leukocyte infiltration. These pathological changes were consistent with the signs of epididymitis that have been reported previously [23][24][25]. We also examined the expression of 13 epididymal bdefensins in epididymal tissue after LPS treatment and found, to our knowledge for the first time, that the expression of 10 bdefensins (including Spag11b and Defb21) significantly decreased whereas expression of the other three (including Defb29) remained unaffected.…”

Comparison of the Effects of Vasectomy and Experimental Cryptorchidism in Rats

“…Epididymal basal lamina was thickened, interstitial collagen became abundant and inflammatory lesions were observed in the tunica propria surrounding the tubules following vasectomy (Nashan et aL , 1990;Flickinger et al , 1990). In the present study, while there no epithelial alterations in the ipsilateral epididymis 3 months after vasectomy, collagen accumulation was seen in the interstitial tissue.…”

Local Regulation of Macrophage Subsets in the Adult Rat Testis: Examination of the Roles of the Seminiferous Tubules, Testosterone, and Macrophage-Migration Inhibitory Factor1

“…This latter observation was considered necessary since vasectomy in certain rat species can cause spontaneous testicular inflammation that could compromise the study [18].…”