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  • Cell & Developmental Biology  (5)
  • Epididymis  (2)
  • 1
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The occurrence of alterations in testicular weight and morphology after vasectomy and vasectomy reversal by vasovasostomy was studied in Lewis rats. Animals were studied 3, 4, and 7 months after bilateral vasectomy or a vasectomy followed 3 months later by vasovasostomy. Other rats served as shamoperated controls. The weights of the testes in vasectomy and vasovasostomy animals fell into two groups - small testes weighing less than 0.88 g and normal-sized testes of 1.2 g or more. When the extent of testicular alterations was estimated in sections for light microscopy by use of a semiquantitative testicular biopsy score count (TBSC), the morphology of the testes corresponded closely to the testis weight (r = .94), small testes having correspondingly low TBSC scores. In severely altered small testes, the seminiferous tubules were narrower than in sham-operated rats, and numbers of germ cells were greatly depleted. Many tubules contained only Sertoli cells and spermatogonia, although spermatocytes were present in a minority of tubules. A few seminiferous tubules contained multinucleate spermatids. Electron microscopy of severely altered tubules revealed closely apposed processes of Sertoli cells, which contained filaments, microtubules, and endoplasmic reticulum. In contrast, testes with normal weight in vasectomy and vasovasostomy groups resembled those of the sham-operated animals. Comparison of distributions of testicular biopsy score counts demonstrated differences between vasectomy and vasovasostomy groups as time after operation increased. At the 3-4-month intervals, approximately one-third of the testes were severely altered in both vasectomy and vasovasostomy groups. However, by 7 months the proportion of altered testes progressed to 60% in animals with a vasectomy, while it remained similar to the earlier intervals in rats that had received a vasovasostomy. These results suggest that vasovasostomy may prevent the progression of testicular alterations that occur after vasectomy, but vasovasostomy does not appear effective in reversing testicular changes.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: 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 tests 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.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 235 (1993), S. 61-73 
    ISSN: 0003-276X
    Schlagwort(e): Vasectomy ; Vasovasostomy ; Epididymis ; Granulomatous inflammation ; Rat ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The response of the male reproductive tract to vasectomy includes inflammation of the interstitial tissue of the epididymis. The pathogenesis of epididymal interstitial reactions and characteristics of the responding cells were studied by electron microscopy in Lewis rats at intervals following bilateral vasectomy, vasectomy followed 1 month later by vasovasostomy, or sham operations. In areas of interstitial reaction, numerous macrophages, monocytes, lymphocytes, neutrophils, and plasma cells occupied the connective tissue. Macrophages, containing many lysosomes and vesicles, aggregated and assumed the appearance of epithelioid cells. Processes of adjacent macrophages interdigitated with one another and closely approached the surfaces of lymphocytes. Many plasma cells with distended rough endoplasmic reticulum appeared in the interstitium. The majority of animals in the vasectomy and vasovasostomy groups exhibited epididymal interstitial changes by 2-3 months; the cauda epididymidis was the region most often affected. The ultrastructural features were indicative of chronic granulomatous inflammation and were consistent with an immune response that includes antigen presentation by macrophages to lymphocytes, lymphocyte differentiation, and local antibody production by plasma cells. The nearly complete absence of sperm or recoghizable parts thereof in the interstitial tissue in the areas of the reactions suggests that these lesions formed in response to soluble antigens leaking from the duct. Vasovasostomy was not effective in reversing or retarding epididymal inflammation at the intervals studied. © 1993 Wiley-Liss, Inc.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 152 (1978), S. 557-585 
    ISSN: 0002-9106
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The ultrastructure of the hamster efferent ducts and epididymis was studied and the results were correlated with previously published data on the composition of luminal fluid obtained by micropuncture. Samples of the efferent ducts and parts of the epididymis designated initial segment, caput, corpus, proximal cauda, distal cauda, and “epididymal vas” were prepared. The efferent ducts contained principal cells characterized by a profusion of apical vesicles and numerous very large vacuoles that were distributed throughout the cytoplasm. Ciliated cells had few vesicles and vacuoles. Occasional cells contained many particles resembling glycogen. In the epididymis, the following trends were observed. The height of the epithelium and the size of the principal cells declined from initial segment to distal cauda. Apical vesicles and vacuoles with a light content were extremely numerous in principal cells of the initial segment and decreased progressively in the more distal regions. In the initial segment, basal and perinuclear rough endoplasmic reticulum was abundant and was distended with a material that resembled newly synthesized protein. Further distally in the epididymis cisternae of the rough endoplasmic reticulum were narrow and contained little intracisternal material. Light cells containing many vesicles, vacuoles, and lysosome-like structures were very prominent in the caudal segments. The epithelium of the epididymal vas had features intermediate between cauda epididymidis and ductus deferens. The cytoplasmic droplet in luminal sperm began to migrate caudally between the caput and corpus epididymidis and reached the posterior extremity of the middle piece in the distal cauda. Some degenerating sperm were observed in the lumen of the distal segments of the epididymis.The abundance of cytoplasmic vesicles and vacuoles in principal cells of the efferent ducts and initial segment of the epididymis correlated with the site of greatest fluid absorption as determined by micropuncture studies, suggesting that these structures are involved in absorption of fluid from the lumen. Between the caput and distal cauda epididymal segments, where absorption of sodium and potassium but not of fluid occurred, there were few vesicles and vacuoles in principal cells, but the “light” cells were large and numerous and contained many vacuoles. The principal cells of the initial segment were best equipped with rough endoplasmic reticulum to synthesize a protein.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 30 (1995), S. 82-100 
    ISSN: 1059-910X
    Schlagwort(e): Vasectomy ; Epididymis ; Vas deferens ; Hydrostatic pressure ; Antisperm antibodies ; Spermatic granulomas ; Inflammation ; Lysosmes ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Allgemeine Naturwissenschaft
    Notizen: Common principles can be discerned in the response of the epididymis to vasectomy, despite species differences. Increases in the size and number of lysosomes are the most frequent changes in the epididymal epithelium. The presence or absence of additional alterations such as changes in the height of the epithelium may be related to variations in distensibility of the vas deferens and epididymis. Direct measurements by micropuncture of epididymal and seminiferous tubule hydrostatic pressure indicate that, contrary to dogma, increased pressure in the distal epididymis after vasectomy is not generally transmitted to the seminiferous tubules. The epididymal interstitium shows microscopic changes indicative of chronic inflammation, with infiltration of macrophages, lymphocytes, and plasma cells, and rats with these lesions have higher antisperm antibody levels than animals lacking epididymal changes. Macrophages and neutrophils may enter the duct through the epididymal epithelium, at sites of rupture of the duct, and in the efferent ductules. Cyst-like spermatic granulomas occur in virtually all species where the epididymis or vas deferens ruptures with escape of spermatozoa. The sites and timing of granuloma formation may depend on the mechanical properties of the tract in different species, and they are probably important in the immune response to vasectomy. Postvasectomy sera in Lewis rats recognize a consensus repertoire of dominant autoantigens that closely resembles the antigens bound by sera from rats immunized with isologous spermatozoa. There are multiple routes for disposal of the sperm that continue to be produced after vasectomy. © 1995 Wiley-Liss, Inc.
    Zusätzliches Material: 19 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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