Early testicular changes after vasectomy and vasovasostomy in Lewis rats

Abstract

The testes of Lewis rats were studied at intervals from 2 weeks to 3 months after bilateral vasectomy, vasectomy followed 1 month later by vasovasostomy, or sham operations. Aims were to determine the nature of early alterations after vasectomy, and to determine whether vasovasostomy after 1 month would result in reversal of vasectomy-induced changes. Approximately one-fourth of the testes in the vasectomy and vasovasostomy groups displayed histological changes, which consisted mainly of depletion of germ cells. The extent of the depletion varied greatly in different seminiferous tubules. In testes altered in this way, no abnormal infiltrations of lymphocytes, macrophages, or other cells were observed in the seminiferous epithelium or in the interstitium. The rete testis and straight tubules were normal in testes with altered seminiferous epithelium. A few testes in the vasectomy and vasovasostomy groups had necrotic centers. The results suggest that depletion of germ cells occurred as a result of shedding from the seminiferous epithelium into the lumen of the tubules. A cellular immune response, such as occurs in experimental allergic orchitis in other species, did not appear to be responsible for the observed loss of germ cells. This suggests a possible role for humoral antibody in this model, since there is an association between testicular changes and serum antisperm antibodies at longer intervals after vasectomy. Testicular alterations were not reversed by performance of a vasovasostomy 1 month after vasectomy.

Ultrastructure of epididymal interstitial reactions following vasectomy and vasovasostomy

“…The patency of vasa deferentia was previously assessed by measuring the rate of fluid flow through cannulated vas deferens segments in vitro. The epididymal alterations occurred despite the fact that nearly 90% of the vasa were patent after vasovasostomy, and the flow of fluid through the vas deferentia of these vasovasostomized rats did not differ significantly from that of the sham-operated controls (Flickinger et al, 1990b). Similarly, vasovasostomy did not appear to reverse testicular alterations in Lewis rats (Flickinger et al, , 1990b.…”

“…The procedure for sham vasovasostomy was identical to that for vasovasostomy with the exception that the intact vas deferens was isolated and the wound was then closed. Testicular morphology and fluid flow through the vas deferens after vasovasostomy were assessed previously (Flickinger et al, 1990b) in the animals considered in the present report. A more extended study of morphology, physiology, and antisperm antibodies was also conducted on rats that received a vasovasostomy 3 months after vasectomy (Flickinger et al, 1986(Flickinger et al, , 1990aHerr et al, 1987Herr et al, , 1989.…”

Comparison of the Effects of Vasectomy and Experimental Cryptorchidism in Rats: I. Testicular Histology

“…In the first and second months following vasectomy, rat testicles were suggested to have distinctive morphological features reflecting the adverse effects of vasectomy, however, the testicular features were similar to the control group testicular structure during the third month of vasectomy (Flickinger et aL, 1990a). In addition, they did not observe inflammatory cell infiltration into the testicular interstitium (Flickinger et al , 1990a) which was also consistent with the findings of the present study. In conclusion, testicular atrophy was suggested by almost every previous study dealing with the effects of vasectomy, and that was also the main feature of the testicular alterations after vasectomy found in the present study.…”

“…Although the vasovasostomy could reverse the anatomical structure of testicles, the fertility rate following vasovasostomy was still low (Flickinger et al, 1990a). Therefore the present study aimed to investigate the effects of vasectomy by comparing the testicular features with the normal and cryptorchid rat testis histology which was used as a permanent infertility model.…”

Degeneration of the seminiferous epithelium following epididymal obstruction in prepubertal rats

“…Other possibilities include reflux of a substance from the epididymis or efferent ductules which adversely affects the testis or systemic changes resulting from altered epididymal physiology (Soler et al, 1990). The development of multinucleated germ cells at 56 days, whether by cell fusion or opening of cytoplasmic bridges between developing germ cells, probably is indicative of stress on the seminiferous epithelium since similar structures have been observed in response to a variety of conditions (Chapin et al, 1983;Hess et al, 1988), including vasectomy (Flickinger et al, 1990), and apparently represent cells that are undergoing apoptosis (Nantel et al, 1996).…”