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

During passage through the epididymis, spermatozoa undergo a number of changes which result in their acquisition of fertility and motility. Some of the changes that occur include loss of the cytoplasmic droplet and changes in sperm morphology, metabolism and properties of the nucleus and plasma membrane. Changes have also been reported in the acrosomic system of mammalian spermatozoa during their transit through the epididymis. In the present study, the quantitative changes of the glycoconjugate content in the acrosome of rat spermatozoa were examined during their passage through the epididymis using lectin-colloidal gold cytochemistry. Various regions of the epididymis (initial segment, caput, corpus and cauda epididymidis) were fixed by perfusion with 1% or 2% glutaraldehyde buffered in sodium cacodylate (0.1 M), dehydrated in ethanol and embedded without osmication in Lowicryl K4M. Lectin-colloidal gold labeling was performed on thin sections using Ricinus communis agglutinin I (RCA I) or Helix pomatia lectin (HPL) to detect D-galactose- and N-acetyl-D-galactosamine-containing glycoconjugates, respectively. The labeling density over the acrosome of the acrosomic system was evaluated as the number of gold particles per microns 2 of profile area using a Zeiss MOP-3 image analyzer. The overall mean labeling densities over the acrosome of spermatozoa for each lectin was estimated from 4 rats and over the four distinct epididymal regions. The mean labeling density of the acrosome with RCA I and HPL showed a similar pattern along the epididymis, although RCA I revealed approximately twice as many gold particles per epididymal region. In either case, there was a significant decrease in the labeling density of the acrosome of spermatozoa between the initial segment or caput epididymidis and cauda epididymidis (p less than 0.01). A similar decrease was also noted between the initial segment and corpus epididymidis (p less than 0.01). No change was found between the initial segment and caput epididymidis. Controls showed a virtual absence of labeling. These results suggest that in addition to a multitude of changes occurring to spermatozoa during epididymal transit, there are also significant quantitative changes in the glycoconjugate content within the acrosome.
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PMID:Quantitative changes of Ricinus communis agglutinin I and Helix pomatia lectin binding sites in the acrosome of rat spermatozoa during epididymal transit. 138 71

The epididymis has three major regions; the caput, corpus and cauda. Sperm were obtained from each region, and their binding ability to egg zona pellucida was assayed. In the case of intact sperm: cauda sperm bound in high number, corpus sperm bound at an intermediate level (an average of 30% of cauda sperm binding level), and caput sperm bound rarely (1% of cauda sperm binding level). In the case of sperm immobilized by pretreatment with LaCl3, when eggs and sperm were shaken in order to allow them to come into collision with each other, the caput and corpus sperm were able to bind to zona pellucida as well as the caudal sperm could. These results suggest that the difference in binding efficiency of the native caput and corpus sperm to bind to the zona pellucida was not due to a defect in a ligand molecule on the plasma membrane but rather to their lack of motility. When a sperm-egg binding assay was done in the presence of a binding inhibitor of caudal sperm, the binding of caudal sperm was significantly inhibited by fetuin or N-acetylgalactosamine, but the binding of caput and corpus sperm was only slightly inhibited by them. We prepared a plasma membrane fraction from each epididymal sperm, and solubilized it with sodium dodecyl sulfate (SDS). Each SDS-solubilizable fraction inhibited the binding of corresponding epididymal sperm to egg zona pellucida but didn't inhibit the binding of sperm from different regions of epididymis. These results suggested that a ligand molecule of caudal sperm was different from that of caput and corpus sperm.
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PMID:Studies on egg zona pellucida-binding molecule (ligand) of mouse sperm. I. Sperm maturation and zona-binding ability. 177 Apr 28

During the annual cycle of the lizard Lacerta vivipara dramatic changes in the secretory activity of the epididymis were observed. These changes and changes in morphology correlate with the plasma and epididymal testosterone concentrations. The secretory proteins contain a major group of immunorelated components referred to as LI to L1X. They consist of a group of nine proteins Mr 19,000 which can be separated according to pI 3.5 to 8.7. Post-translational modifications may be responsible for their pI diversity. All the L proteins are glycosylated (fucose, N-acetylgalactosamine and or N-acetylglucosamine) but only LVI glycosylation was inhibited with tunicamycin. Phosphorylation is unique to LV protein and none of the L proteins are sulfated. All L proteins appeared sequentially during the annual cycle and in organotypic culture when incubated in the presence of testosterone (150, 500, 1000 nM) in a time dependent manner.
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PMID:Synthesis and post-translational modifications of an epididymal androgen dependent protein family. 177 99

Ram sperm, isolated from the caput, corpus, and cauda epididymidis, plus ejaculated cells were washed free of loosely bound components and tested for their ability to bind fluorescein-conjugated lectins (Con A, SBA, RCA, PNA, ECA and WGA) as assessed by epiluminescent-fluorescence light microscopy and flow cytometry. Detailed preliminary studies established an appropriate lectin-to-sperm ratio and incubation conditions for quantitative comparisons of sperm cell types and permitted a detailed analysis of both the amount of lectin bound as well as its distribution on the various aspects of the cell surface. Con A (mannose positive) bound weakly over the entire surface, with little change associated with maturation in the male tract. SBA (N-acetylgalactosamine positive) bound moderately strongly to caput sperm, with an emphasis on the apical ridge portion of the cell; during epididymal transit this binding was greatly diminished and was regained upon ejaculation. RCA, PNA, and ECA (galactose positive) gave generally equivalent results, where initially strong binding to the entire sperm surface decreased (over all parts of the surface except the anterior head) during epididymal maturation, with no change associated with ejaculation. WGA (sialic acid positive) binding initially was weak, but increased with epididymal transit and ejaculation. In vitro incubations with beta-galactosidase and neuraminidase confirmed the assignments given above. These data, when coupled with previous reports describing the heterogeneous distribution of proteins and lipids and changes in their distribution associated with epididymal maturation, serve to quantitatively describe changes in those aspects of the cell surface that are probably responsible for the acquisition of the capacity of the sperm to bind successfully to the oocyte.
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PMID:Changes in lectin-binding features of ram sperm surfaces associated with epididymal maturation and ejaculation. 337 79

Efferent reproductive ducts of male mice, including ductuli efferentes, epididymis, and vas deferens, were fixed and embedded in paraffin, and sections were stained with a battery of lectin-horseradish peroxidase conjugates to localize specific sugars or sugar sequences in glycoconjugates. Cilia and the apical surfaces of ciliated cells in the ductuli efferentes stained intensely with lectin specific for sialic acid and terminal alpha-N-acetyl-D-galactosamine. Flask cells and clear cells in the epididymis reacted positively and similarly with most lectins used, providing evidence that these cell types are related. In contrast, disparities in lectin staining suggest that flask cells and clear cells are a cell type distinct from principal cells. Basal cells were not present in the ductuli efferentes but formed a continuous layer in the epididymis and vas deferens. Basal cells contained oligosaccharides terminated by sialic acid and alpha-D-galactose and varying amounts of terminal beta-D-galactose and alpha-N-acetyl-D-galactosamine. Basal cells also stained variably with lectins specific for the core region of complex type N-glycosidic side chains. The basal cells varied structurally, having long spinous apical processes approaching or reaching the lumen in region I of the epididymis and being low cuboidal or squamoid and lacking apical processes in epididymal regions II-V and in the vas deferens. The contiguous nature of the basal cells and the presence of glycoconjugates bearing terminal alpha-galactosyl residues in all basal cells suggest a possible role for these cells in a regulatory influence on transepithelial movement of fluid and/or ions in the epididymis and vas deferens.
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PMID:Histochemical evaluation of glycoconjugates in the male reproductive tract with lectin-horseradish peroxidase conjugates: II. Staining of ciliated cells, basal cells, flask cells, and clear cells in the mouse. 382 61

Lectins from the horseshoe crab (Limulus polyphemus) and the garden snail (Helix pomatia) were tested for insulinomimetic activities in isolated rat epididymal adipocytes. The sialic acid binding horseshoe crab lectin suppressed epinephrine-induced lipolysis and augmented lipogenesis from D-[3-3H]-glucose while the N-acetylgalactosamine binding snail lectin was inactive. The results suggest that the insulin receptor on rat adipocytes contains sialic acid in its carbohydrate moiety but does not possess non-reducing alpha-D-galactopyranosyl or 2-acetamido-2-deoxy-alpha-D-galactopyranosyl end groups.
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PMID:Horseshoe crab (Limulus polyphemus) lectin but not garden snail (Helix pomatia) lectin elicits insulin-like activities in vitro. 389 76

Immobilin, the highly viscoelastic glycoprotein isolated from rat cauda epididymal fluid, exhibits all of the key biochemical characteristics of a mucin: 1) it has a very high molecular weight (will not pass through a 10(6) dalton cut-off filter; 2) it contains 56% carbohydrate, with low or undetectable levels of mannose, xylose and uronic acid; 3) the carbohydrates (primarily galactose, N-acetylglucosamine and N-acetylgalactosamine) are arranged in short, oligosaccharide chains (4-20 monosaccharides per chain); 4) these oligosaccharide chains can be cleaved by NaOH in the presence of NaBH4, suggesting O-glycosidic linkages; and 5) the protein core is pronase-resistant. Immobilin, however, contains no detectable sialic acid, and 67% of the oligosaccharides are uncharged, indicating that immobilin is less acidic than most other mucins.
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PMID:Rat cauda epididymal fluid is a mucus. 405 30

Six specific agglutinins were used to identify the terminal sugar residues in the surface oligosaccharides of rabbit and hamster spermatozoa by specific agglutination. Species differences in epididymal sperm were found in the terminal residues, resembling alpha-D-mannose, D-galactose, N-acetyl-D-glucosamine, and N-acetyl-D-galactosamine. Species similarities were found in terminal residues, resembling L-fucose and N-acetylneuraminic acid. When ejaculated rabbit sperm were compared to epididyimal sperm, the latter were more agglutinable with a specific agglutinin recognizing N-acetyl-D-glucosamine.
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PMID:Terminal saccharides on sperm plasma membranes: identification by specific agglutinins. 504 Oct 26

PDC-109 (13 kDa) is the most abundant component, and the major heparin-binding protein, of bovine (Bos taurus) seminal plasma. Here, we show that PDC-109 contains a single O-linked oligosaccharide (NeuNAc alpha(2-6)-Gal beta(1-3)-GalNAc-) attached to Thr11. Immunoquantitation of PDC-109 indicates that its concentration in seminal plasma is 15-20 mg/ml. Though PDC-109 is not present on epididymal sperm, ejaculated spermatozoa on average are coated with (9.5 +/- 0.3) x 10(6) molecules of PDC-109/cell. This value remained constant in swim-up sperm and decreased to (7.7 +/- 0.4) x 10(6)/spermatozoon after incubation for 24 h in capacitation medium at 39 degrees C. These data substantiate the hypothesis that PDC-109 may be one of the seminal plasma components that enhance the fertilizing capacity of bull spermatozoa upon interaction with heparin-like glycosaminoglycans present in the female genital tract.
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PMID:Localization and structural characterization of an oligosaccharide O-linked to bovine PDC-109. Quantitation of the glycoprotein in seminal plasma and on the surface of ejaculated and capacitated spermatozoa. 807 May 64

A histochemical study using lectins to identify glycoconjugates present in the efferent ducts and ductus epididymidis of men without testicular or related disease was carried out. The lectins used and the oligosaccharide residues linked were: wheat germ agglutinin (WGA) for beta-N-acetylglucosamine and sialic acid, concanavalin A (ConA) for alpha-mannose, Ulex europaeus agglutinin (UEA-I) for alpha-fucose, Dolichos biflorus agglutinin (DBA) for alpha-N-acetylgalactosamine, soy bean agglutinin (SBA) for beta-N-acetylgalactosamine, and peanut agglutinin (PNA) for beta-galactose. The lectin-binding pattern in the human epididymis presents similarities and differences to those observed in other mammals which also showed differences between species. The present results revealed that regional differences along the human ductus epididymidis were less pronounced than those reported in other mammals. The epithelial cells in the efferent ducts reacted positively to WGA. All along the length of the ductus epididymidis, the principal cells and the luminal content showed staining affinity for WGA and ConA. The epididymal principal cells and luminal content also reacted positively to DBA for alpha-N-acetylgalactosamine but only in the cauda epididymidis. A positive reaction to UEA-I was observed only in the luminal content of the cauda epididymidis. This finding suggests that changes in the oligosaccharide chains of secretions leading to a positive UEA-I reaction occur in the cauda epididymidis. The epididymal principal cells showed positive reactions to SBA and PNA over the apical microvilli but not in the cytoplasm. The reaction was observed in the caput and corpus epididymidis but not in the cauda. Positive reactions to SBA and PNA were also detected in the epididymal fluid and in the cytoplasm of mitochondria-rich cells (a minor population of epididymal epithelial cells). These cells also reacted to other lectins such as WGA, ConA and DBA, which were also detected in the principal cells.
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PMID:Lectin histochemistry in the human epididymis. 869 16


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