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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The histology and fine structure of the testis, epididymis and sex accessory glands were studied in young adult male rats administered testosterone enanthate, 120 microgram/100 g body weight, three times weekly for 4, 8, or 12 weeks. The weights of the testis and epididymis decreased, and animals treated for 11 weeks were infertile. Alterations were found in the seminiferous tubules of all rats treated for 8 or 12 weeks, including the presence of many degenerating germ cells and a large decrease or absence of late spermatids. Study of different stages of the cycle of the seminiferous epithelium showed that the greatest number of degenerating germ cells, step 7 spermatids and pachytene primary spermatocytes, occurred at stages VII-VIII of the cycle. Some normal appearing spermatogonia, primary spermatocytes and early spermatids remained in most seminiferous tubules. Sertoli cells contained many lipid droplets and lysosome-like bodies, and degenerating cells were surrounded by Sertoli cell cytoplasm. The Leydig cells of treated animals were greatly reduced in size. Sperm progressively disappeared from the lumen of the middle segment and proximal part of the terminal segment of the epididymis after treatment for 8 or 12 weeks. Changes in the middle segment also included the appearance of intraepithelial cavities containing debris, and the presence within the epithelium of phagocytic cells that resembled leukocytes. The lumen of the proximal part of the terminal segment was often collapsed, while in the distal part of the terminal segment, the lumen was filled with cellular debris and degenerating sperm. Organelles of the principal cells of the epididymal epithelium appeared to be qualitatively unaltered. The weight of the sex accessory glands remained close to normal, and the presence of normal ultrastructural features suggested that production of secretions continued.
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PMID:Effects of testosterone enanthate on the structure of the male reproductive tract of the rat. 73 75

The toxicities of theobromine and cocoa extract on the reproductive tract of male rats were compared in the present study. A cocoa powder extract containing 117 mg theobromine/g extract was prepared using 85% boiling methanol. Sprague-Dawley rats were weighed and dosed daily for 31 days with vehicle, 250 mg/kg theobromine, 2.14 g/kg cocoa extract (117 mg theobromine/g extract), or 0.43 g/kg cocoa extract by oral gavage. The animals were sacrificed on day 32. One testis and epididymis were removed and weighed. The epididymis was saved for the determination of epididymal sperm reserves. The remaining testis was fixed by whole body glutaraldehyde perfusion and processed for morphologic examination. A decrease in body weight gain and epididymal weights were observed in theobromine and high-dose cocoa-extract-treated groups. Theobromine and high-dose cocoa extract caused vacuolation within the Sertoli cell, abnormally shaped spermatids, and failed release of late spermatids in treated animals. Most of the vacuolations were found in the earlier and middle stage seminiferous tubules (stages I to VIII). However, the frequency of some parameters of testis alterations were significantly lower in the high-dose cocoa-extract-treated group compared to the theobromine-treated group. These data demonstrate the ability of a cocoa extract containing theobromine to alter testis structure in a similar pattern but with reduced intensity compared to that observed after oral exposure to pure theobromine.
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PMID:Reproductive toxicity of theobromine and cocoa extract in male rats. 152 Oct 8

The present study examined the relationship between the functional status of Sertoli cells and the maintenance and restoration of spermatogenesis in immature hypophysectomized (HPX) rats given various doses of exogenous testosterone with or without daily injections of FSH for 90 days. Subcutaneous implantation of a 2- to 10-cm testosterone capsule (TC) increased serum testosterone levels of HPX rats 2-10 times above the normal control levels, but did not significantly increase the testicular testosterone level. Daily injections of FSH significantly increased the accumulation of testosterone in testes of TC-implanted HPX rats. Maintenance of early spermiogenesis was observed in all TC-implanted animals. Although elongated spermatids were present, step 18-19 spermatids at the luminal edge of stages VII-VIII epithelium were only observed in rats bearing 10-cm TC implants. Daily injection of FSH resulted in the completion of spermiogenesis in all TC-implanted animals, and the number of step 18-19 spermatids was dependent on the length of TC implants used. These results demonstrate the importance of the synergism of FSH and testosterone in the final steps of spermiogenesis. The androgen-binding protein (ABP) content per testis of the HPX rats was stimulated by TC implants. However, a significant increase in epididymal ABP was only noted in rats bearing 10-cm TC implants. Injection of FSH resulted in a significant increase in the testicular ABP content in rats bearing 2- or 5-cm TC, but not in those with 10-cm TC implants. In addition, the epididymal ABP content was significantly stimulated by FSH in all TC-implanted animals. The ABP status in the testis and its transport toward the epididymis are closely related to the extent of maintenance of spermiogenesis. It is speculated that the production of ABP by Sertoli cells and the biochemical properties of ABP molecules may have some role in the control of the final steps of spermiogenesis.
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PMID:Synergistic effects of follicle-stimulating hormone and testosterone on the maintenance of spermiogenesis in hypophysectomized rats: relationship with the androgen-binding protein status. 190 1

Rats were exposed to 0, 0.1, 1, and 12 ppm of hexafluoroacetone (HFA) for 6 h/day, 5 days/week for 90 days. The exposed rats were killed after 30 or 90 days exposure, and 28 or 84 days post-exposure (PE). There were no exposure-related pathological lesions in the rats exposed to 0.1 or 1.0 HFA for 90 days. After 30 days exposure to 12 ppm HFA, rats showed lower body weight gain, testicular atrophy, and oligospermia or aspermia in the epididymal tubules. At 30 days exposure, the atrophic testes had marked depletion of round spermatids in spermatogenic stages I-VIII and elongated spermatids in spermatogenic stages IX-XIV, but mature spermatids appeared only slightly decreased. Numerous spermatocytes in meiotic division in spermatogenic stage XIV were necrotic. At 90 days exposure, the testes showed severe atrophy with almost all seminiferous tubules affected and both immature and mature spermatids had disappeared from the seminiferous tubules. The epididymal tubules were devoid of spermatozoa. After 28 days PE, regeneration of atrophic testes was evident but varied markedly among the exposed rats. The number of seminiferous tubules producing elongated and mature spermatids was significantly lower than that of normal testes. Many seminiferous tubules had not regained normal spermatogenesis and the epididymal tubules showed marked oligospermia. After 84 days PE, normal spermatogenesis was still only partially restored to the atrophic testes, with many of the regenerating tubules still devoid of normal spermatogenesis.
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PMID:Testicular toxicity of rats exposed to hexafluoroacetone (HFA) for 90 days. 204 29

Adult male rats were dosed orally on d 0 with 0 or 2000 mg/kg of boric acid and killed on posttreatment d 2, 14, 28, and 57, or dosed with 0, 250, 500, 1000, or 2000 mg/kg of boric acid and killed on posttreatment d 14. At d 14, atypical structures that appeared to be enlarged irregular cytoplasmic lobes of Step 19 spermatids were observed in Stage VIII seminiferous tubules of rats dosed with 1000 and 2000 mg/kg. Abnormal retention of Step 19 spermatids and residual bodies was also observed in Stage IX-XIII tubules of these rats. The retained spermatids and residual bodies were seen in both the luminal and basal regions of the epithelium. A substantial increase in the testicular sperm head count occurred in animals dosed with 2000 mg/kg. Abnormal caput epididymal sperm morphology and reduced caput epididymal sperm reserves were observed at 1000 mg/kg and higher. Serum LH, FSH, TSH, and prolactin values were not affected at any dosage. At d 28, rats dosed with 2000 mg/kg exhibited continued retention of Step 19 spermatids into Stage X, abnormal caput and cauda sperm morphology, and decreased percentages of motile cauda spermatozoa with reduced straight-line swimming velocities. By d 57 substantial recovery was apparent; some retention of Step 19 spermatids into Stage X tubules was still present in two out of six rats but the sperm parameters were comparable to controls. The study indicated that acute oral exposure to boric acid adversely affected spermiation and sperm quality in the adult male rat. At the dosages used the effects appeared reversible. The no-effect level was 500 mg/kg.
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PMID:Effect of acute exposure to boric acid on the male reproductive system of the rat. 221 25

Synchronization of spermatogenesis would provide an ideal model for the investigation of stage-dependent changes in the secretion of paracrine factors. In vitamin A-deficient animals subsequently injected with vitamin A, over 80% of seminiferous tubules were synchronized within three to five stages of the seminiferous cycle. Following replenishment of vitamin A, spermatogenic stages IV-VI (35 days), VI-VIII (38 days), IX-XII (41 days), I-IV (45 days) and V-VII (48 days) were observed. Despite synchronization of spermatogenesis at all stages, spermatogenesis was markedly impaired when evaluated in a quantitative fashion. At all times evaluated, numbers of round spermatids were reduced compared with age-matched controls. Numbers of pachytene spermatocytes reached control values only after 45 days of vitamin A replenishment. Elongate spermatids were almost totally absent up to 41 days after vitamin A replenishment. Testicular and epididymal weights were also reduced, although testicular weights showed a significant recovery over the time-course of the study. Serum and pituitary concentrations of LH and FSH were raised at the commencement of the study, with serum gonadotrophins returning to control values 48 days after vitamin A replenishment. Both testicular and serum testosterone concentrations in treated animals tended to be higher than in the controls. Although synchronization of spermatogenesis was achieved, testicular testosterone concentrations did not reflect the stage-dependent cyclical changes observed in earlier studies. Testicular concentrations of testosterone were raised throughout the period of observation with the exception of animals synchronized around stages II-IV of the spermatogenic cycle. No correlation between the most frequent stages and intratesticular testosterone was found (r = 0.06, P greater than 0.1). Previous observations that testosterone concentrations are selectively increased at stages VII-VIII of the spermatogenic cycle are not supported by the present study.
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PMID:Quantitative analysis of germ cell numbers and relation to intratesticular testosterone following vitamin A-induced synchronization of spermatogenesis in the rat. 251 47

Rats were treated with a single high dose of methoxy acetic acid (MAA; 650 mg/kg) specifically to deplete seminiferous tubules of pachytene and later spermatocytes. The impact of this selective depletion on subsequent spermatogenesis, sperm output and fertility was then evaluated at intervals ranging from 3 days to 10 weeks. Cauda epididymal sperm number was reduced progressively beyond 2 weeks post-treatment and reached a nadir at 5-6 weeks (28-34% of control values) before recovering progressively back to control levels at 10 weeks. Sperm motility was reduced significantly at 4-7 weeks post-treatment with a nadir at 6 weeks (35% of control values). Thus, at 5-6 weeks after MAA treatment, motile sperm output was reduced by 82-88%. Despite these changes, there was little evidence for infertility in the majority of treated males during a serial mating trial. Evaluation of seminiferous tubule morphology combined with germ cell counts at stage VII of the spermatogenic cycle confirmed that, initially, MAA induced the specific loss of pachytene and later spermatocytes at all stages other than early to mid stage VII. Maturation depletion of germ cells at later intervals was consistent with the initial effects of MAA, although at 21 days post-treatment a number of unpredicted (? secondary) changes in spermatogenesis were observed. These were (a) a reduction in number of pachytene spermatocytes at late stage VII/early stage VIII, (b) retention of sperm at stages IX-XIV, and (c) increased degeneration of pachytene spermatocytes and round spermatids at stage VII and of secondary spermatocytes at stages XIV-I. Whilst none of these changes was severe, together they probably accounted for the unexpectedly prolonged drop in sperm output. It is concluded that whilst deleterious changes in spermatogenesis may occur secondarily following MAA treatment, for the most part spermatogenesis proceeds normally and fertility is largely maintained despite a massive but transient decrease in sperm output.
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PMID:Evaluation of the effect of selective germ cell depletion on subsequent spermatogenesis and fertility in the rat. 271 72

The stages of the rat seminiferous epithelial cycle have been isolated for flow cytometric analysis of DNA and for culture, using transillumination-assisted microdissection. Precise stages have been identified by phase contrast microscopy of live cell squashes from adjacent segments. Each stage of the cycle showed a characteristic flow cytometric pattern with haploid (1C), diploid (2C) and tetraploid (4C) peaks. Stages I to VIII of the cycle showed an additional hypofluorescent (0.25-0.70C) peak due to a reduced dye-binding capacity of maturation phase-spermatids at steps 15 through 19. The appearance of the hypofluorescent haploid peak coincided with the second nucleoprotein transition at step 15 of spermiogenesis and the homogeneous condensation of the chromatin seen in electron microscopy. As a concomitant of the formation of disulphide bonds during epididymal maturation, the fluorescence intensity decreased further to reach a relative value of 0.07C in the cauda epididymidis. The constant 1C peak was raised by round and elongating spermatids (steps 1-14), 2C by spermatogonia, secondary spermatocytes and Sertoli cells, and the 4C peak by primary spermatocytes and spermatogonia at G2 or M phase of the mitotic cycle. The proportion of each peak accurately reflected the relative proportion of cells in most stages of the cycle when compared with morphometric measurements of histologic preparations. DNA flow cytometry is a suitable method for quantitative evaluation of cultured seminiferous tubule segment DNA. Although the relative yield of the meiotic reductive divisions in vitro is comparable with that observed in vivo, steps 9 and 15 of spermiogenesis involving nucleoprotein transitions and spermiation itself did not occur under the present culture conditions.
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PMID:Flow cytometric DNA analysis of defined stages of rat seminiferous epithelial cycle during in vitro differentiation. 407 24

Mouse and guinea pig epididymal tissues have been investigated by light and electron microscopic autoradiography after long intervals ranging from 24 h to 5 days postinjection (p.i.) of the glycoprotein precursors, L-fucose-6-3H or D-glucosamine-1-3H. Using modified fixations to enhance glycoprotein preservation in situ, we found intense labelling of luminal contents in at least some of the epididymal segments after all the intervals investigated. At 24 h p.i., the label in guinea pig was associated with spermatozoa during remodelling of the acrosome in segment II, and at 3 days p.i., radioactivity was trapped within sperm head associations ("rouleaux") in segment IV of the epididymis. At this time, similar rouleau labelling extended from segment IV to segment VIII. In mouse, the luminal contents of the cauda epididymis were still intensely labelled at 5 days p.i.; analysis of the electron microscopic autoradiograms showed that relative grain concentration over the spermatozoa was twice that of the epididymal plasma. This concentration was especially elevated in the region of the sperm head. These findings taken together were interpreted as the binding of secreted epididymal glycoproteins to spermatozoa during sperm transit through the epididymis. In contrast to luminal contents, the labelling of the epididymal epithelium was generally lower, except on the clear cells which showed more pronounced labelling than the neighboring principal cells in mouse cauda epididymis at 5 days p.i. This label probably originated from the resorption of luminal glycoproteins.
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PMID:Binding of secreted glycoproteins to spermatozoa in the mammalian epididymis: a fine-structure autoradiographic study. 670 37

In previous studies we identified an epididymal gene that exhibits homology to the cystatin family of cysteine protease inhibitors. The expression of this gene, termed CRES (cystatin-related epididymal and spermatogenic), was shown to be highly restricted to the proximal caput epididymal epithelium with less expression in the testis and no expression in the 24 other tissues examined. In this report, studies were carried out to examine CRES gene expression in the testis as well as to characterize the CRES protein in the testis and epididymis. In situ hybridization experiments revealed that within the testis CRES gene expression is stage-specific during spermatogenesis and is exclusively expressed by the round spermatids of Stages VII-VIII and the early elongating spermatids of Stages IX and X. Immunohistochemical studies demonstrated that CRES protein was transiently expressed in both the testis and epididymis. Within the testis the protein was localized to the elongating spermatids, whereas within the epididymis CRES protein was exclusively synthesized by the proximal caput epithelium and then secreted into the lumen. Surprisingly, the secreted CRES protein had completely disappeared from the epididymal lumen by the distal caput epididymidis. Western blot analysis of testicular and epididymal proteins showed that the CRES antibody specifically recognized a predominant 19 kDa CRES protein and a less abundant 14 kDa form. These observations suggest that the CRES protein performs a specialized role during sperm development and maturation.
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PMID:Transient appearance of CRES protein during spermatogenesis and caput epididymal sperm maturation. 761 4


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