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

In the present study, the topographical distribution of carbohydrate binding sites on the plasma membrane of bovine epididymal spermatozoa was investigated using 15 different fluorescent neoglycoproteins and asialoglycoproteins. With mannose-bovine serum albumin (BSA)-fluoresceinthiocarbamyl (FTC), mannose-6-phosphate-BSA-FTC, lactose-BSA-FTC, maltose-BSA-FTC, asialolactoferrin-FTC and asialotransferrin-FTC a marked fluorescence was observed in the postacrosomal area. These results further substantiate the concept that carbohydrate binding sites of the spermatozoan plasma membrane and corresponding carbohydrates of the zona pellucida play a significant role in gamete interactions.
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PMID:Surface sugar binding components of bovine spermatozoa as evidence by fluorescent neoglycoproteins. 336 43

alpha-Lactalbumin, a modifier protein that changes the substrate specificity of galactosyltransferase, to promote the synthesis of lactose, is found in the mammary glands of lactating mammals and in milk. Molecules similar to mammary gland alpha-lactalbumin but distinct in their modifier activity have been found in rat epididymal fluid. We report here, using a rat mammary gland alpha-lactalbumin cDNA clone as a hybridization probe, RNA sequences homologous to alpha-lactalbumin mRNA were detected in total RNA from the rat epididymis. This finding suggests that alpha-lactalbumin or similar molecules, in addition to regulating lactose synthesis in the mammary gland, may have other important functions in mammalian reproduction.
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PMID:The presence of the milk protein, alpha-lactalbumin and its mRNA in the rat epididymis. 641 37

Hamster eggs with postovulatory oviduct contents were added to a simple defined medium, without serum albumin, but supplemented with different combinations of energy sources. They were then inseminated by epididymal spermatozoa. In a medium containing D-glucose but without pyruvate and/or lactate, high proportions of acrosome-reacted spermatozoa (78-94%) and eggs undergoing fertilization (89-96%) were obtained 9-9.5 h after insemination. With only pyruvate or lactate as substrates, or with both pyruvate and lactate, acrosome reactions occurred in only 2-4% of the sperm. When D-glucose ranging in concentration from 2.78 to 8.34 mM was added, a high proportion (82-95%) of the eggs inseminated were found to be fertilized. Substituting D-galactose, L-glucose, L-fucose, D-lactose, or D-saccharose for D-glucose resulted in very low numbers of acrosome-reacted sperm (0-12%) and fertilized eggs (0-7%). However, in the presence of metabolizable sugars, such as D-mannose or D-fructose, the acrosome reaction was seen in 78-85% of the sperm examined and 87-95% of the eggs tested were fertilized.
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PMID:The importance of the presence of metabolizable sugars in a medium for in vitro fertilization of hamster eggs with postovulatory oviduct contents. 707 70

The same low M(r) protein fraction of epididymal luminal fluid as that studied previously by Hamilton in 1981 was assayed for alpha-lactalbumin (alpha-lac) activity with bovine milk galactosyltransferase (GalTase) as the enzyme source and bovine serum albumin (BSA) to make the total protein concentrations of all the samples in each assay constant. No alpha-lac activity could be detected in this fraction. When glucose was used as an acceptor, radioactivity passing through the ion exchange column used to retain the remaining UDP-galactose did increase with the amount of the proteins of the low M(r) fraction, but this increase was observed not only for samples with an acceptor but also for samples without. The increased radioactive product co-migrated in high-voltage electrophoresis with galactose, not lactose. When GlcNAc was used as an acceptor, the situation was the same, and the increased radioactive product co-migrated with galactose, not LacNAc. No inhibition of bovine milk GalTase activity by the low M(r) proteins was observed. Addition of protein, either BSA or the low M(r) fraction of epididymal luminal fluid, to assay medium that contained no proteins other than GalTase enhanced the GalTase activity both in forming lactose in the presence of glucose and also LacNAc in the presence of GlcNAc. It appears that the earlier reports of alpha-lac-like activity in epididymal fluids and extracts may have been due to the presence of enzymes liberating free galactose from UDP-galactose and/or a stimulatory non-specific effect of the protein in the solutions on the lactose synthesis activity of the GalTase.
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PMID:No alpha-lactalbumin-like activity detected in a low molecular mass protein fraction of rat epididymal extract. 826 6

This study reports the development of a reliable method for cryopreservation of rat epididymal spermatozoa and the production of live young by artificial insemination using these cryopreserved spermatozoa. The motility and membrane integrity of rat spermatozoa were investigated after spermatozoa had been subjected to physical stress and frozen with various concentrations of glycerol (0, 3 and 6%) either in the presence or absence of Equex Stem as cryoprotective agents. The ability of cryopreserved spermatozoa to generate normal offspring by intrauterine insemination was also evaluated. Rat spermatozoa that had been centrifuged at 700 g for 5 min showed a significant decrease in motility compared with non-centrifuged spermatozoa. In addition, after centrifugation three times the percentage of membrane-intact spermatozoa decreased to approximately 0%. The percentage of membrane-intact spermatozoa was significantly higher (P < 0.01) in semen samples that had been frozen in medium without glycerol than in samples frozen in medium with 3% glycerol. Although the addition of 0.7% Equex Stem to medium without glycerol or with 3% glycerol did not influence rates of sperm motility after freezing and thawing, the percentage of membrane-intact spermatozoa was improved by the presence of 0.7% Equex (P < 0.05). Therefore, rat spermatozoa were handled gently to avoid physical stress and were frozen in medium containing 23% egg yolk, 8% lactose monohydrate and 0.7% Equex Stem, at pH 7.4 adjusted with 10% Tris(hydroxymethyl)aminomethane solution. Thirteen female rats were inseminated into the oviductal end of both uterine horns with frozen-thawed spermatozoa. Forty-one normal live offspring were obtained from nine of the inseminated females. These results indicate that frozen-thawed rat spermatozoa can generate normal offspring. To our knowledge, this procedure is the first successful production of offspring using spermatozoa cryopreserved in liquid nitrogen.
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PMID:Generation of live rat offspring by intrauterine insemination with epididymal spermatozoa cryopreserved at -196 degrees C. 1159 11

We attempted to cryopreserve spermatozoa from closed colonies (Jcl:SD and Jcl:Wistar), and inbred (BN/Crj, F3441 DuCrj, LEW/Crj, Long-Evans and WKY/NCrj), mutant (Zitter [WTC.ZI-zi] and Tremor [TRM]), transgenic (human A-transferase [A], and green fluorescent protein [GFP]) strains of rats. Rat epididymal spermatozoa suspended in cryopreservation solution (23% egg yolk, 8% lactose monohydrate, and 0.7% Equex Stm, pH 7.4, adjusted with 10% Tris [hydroxymethy] aminomethane) were frozen and stored at -196 degrees C. After thawing at 37 degrees C, the spermatozoa were instilled into the tip of each uterine horn of the recipients. A total of five recipient females for each strain were inseminated with cryopreserved spermatozoa, and normal live offspring of all strains (Jcl:SD: 11, Jcl:Wistar: 13, BN/Crj: 9, F344/DuCrj: 28, LEW/Crj: 4, Long-Evans: 6, WKY/NCrj: 8, TRM: 24, WTC.ZI-zi: 27, A: 30 and GFP: 20) were obtained.
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PMID:Cryopreservation of spermatozoa from closed colonies, and inbred, spontaneous mutant, and transgenic strains of rats. 1472 12

The objective of this study was to compare the in vitro fertilizing capacity of porcine spermatozoa from fresh and frozen-thawed semen and frozen-thawed epididymal spermatozoa obtained from identical boars. Prior to IVF, fresh spermatozoa were capacitated in TCM 199. Frozen semen samples were stored in 0.25-ml plastic straws using a lactose/glycerol/orvus-es-paste extender. Cumulus-oocyte-complexes (COC) obtained from superovulated prepuberal gilts were fertilized in vitro within 2 h after aspiration with one of the semen samples. After final dilution for IVF, frozen-thawed epididymal semen samples showed motility rates (72.2 +/- 5.6%) similar to those of spermatozoa in fresh semen (76.4 +/- 4.5%), while sperm motility decreased in frozen-thawed ejaculated semen (40.2 +/- 9.4%). Considerable individual differences in sperm motility between boars were observed for ejaculated semen but not for epididymal semen. Enhanced fertilizing capacity of frozen-thawed epididymal spermatozoa was confirmed by pronucleus formation and cleavage rates, with significantly more embryos developing to the 2- and 4-cell stages compared with the groups fertilized with fresh or with frozen-thawed ejaculated semen (59.7 vs 14.6 and 16%). In conclusion, consistent in vitro fertilization rates with minimal semen variability are obtained using frozen-thawed epididymal semen. Following a modified freezing protocol, epididymal spermatozoa can easily be frozen in small containers for IVF, with higher resultant motility and fertilization rates than with ejaculated semen.
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PMID:In vitro fertilization of porcine oocytes with fresh and frozen-thawed ejaculated or frozen-thawed epididymal semen obtained from identical boars. 1672 28

Epididymal spermatozoa were harvested from male alpacas and frozen after extension and cooling to 4 degrees C in citrate-, Tris- and lactose-based diluents (Experiment 1) and as pellets in 0.25- and 0.5-mL straws on either dry ice or over liquid nitrogen vapour (Experiment 2) to determine the effects diluents and packaging on their motility and acrosome integrity. In Experiment 1, sperm motility was higher after cooling to 4 degrees C and after freeze-thawing (0 but not 3 h post-thaw) for spermatozoa extended in the lactose- than the citrate- or Tris-based diluent (P < 0.05). Post-thaw acrosome integrity after cooling to 4 degrees C and post-thaw (0 h) was reduced for spermatozoa frozen in citrate- compared with lactose- or Tris-based diluents, but was similar for all groups 3 h after thawing. In Experiment 2, sperm motility immediately after thawing was higher for pellet freezing than for 0.25- or 0.5-mL straws on dry ice or liquid nitrogen vapour (P < 0.05), although by 3 h post-thaw motility was similar for pellets and straws (P > 0.05). Acrosome integrity was similar for all groups immediately after thawing and 3 h post-thaw. Cryopreservation of epididymal alpaca spermatozoa is feasible, with retained motility and acrosome integrity post-thaw. Freezing as pellets in a lactose-based diluent is recommended.
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PMID:Cryopreservation of epididymal alpaca (Vicugna pacos) sperm: a comparison of citrate-, Tris- and lactose-based diluents and pellets and straws. 1789 81

The objective of this study was to develop an ideal freezing extender and method for rat epididymal sperm cryopreservation. Epididymal sperm collected from 30 Wistar males was frozen, and experiments were conducted to study its post-thaw characteristics when freezing with raffinose-free buffer or various concentrations of raffinose and egg yolk dissolved in distilled and deionised water, PBS, or modified Krebs-Ringer bicarbonate (mKRB)-based extender. Different concentrations of glycerol, Equex STM, or sodium dodecyl sulfate (SDS) dissolved in either PBS or mKRB containing egg yolk were also tested. Based on the data from these experiments, further experiments tested how different sugars such as raffinose, trehalose, lactose, fructose, and glucose dissolved in mKRB with Equex STM, SDS and egg yolk supplementation affected the post-thaw characteristics of cryopreserved sperm. Cryosurvival of frozen-thawed sperm were judged by microscopic assessment of the sperm motility index (SMI), and acrosome integrity was measured using FITC-PNA staining. Thawed sperm were subjected to 3h of a thermal resistance test. Beneficial effects on the post-thaw survival of sperm were obtained when 0.1M raffinose in mKRB was used with 0.75% Equex STM, 0.05% SDS, and 20% egg yolk. Sperm cryopreserved with this treatment exhibited a higher motility index and maintained greater SMI and acrosome integrity throughout incubation when compared to sperm frozen in various concentrations of other cryoprotectants and trehalose, lactose, fructose, glucose. In conclusion, cryopreservation in an extender solution of raffinose dissolved in mKRB containing Equex STM, SDS and egg yolk greatly enhances the freezability of rat epididymal sperm.
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PMID:Freezability of rat epididymal sperm induced by raffinose in modified Krebs-Ringer bicarbonate (mKRB) based extender solution. 1792 21

A Tris-citric acid-glucose (TCG) diluent containing low concentrations (6%) of egg yolk, and a TCG extender containing lactose (without egg yolk), were compared for use in the cryopreservation of Spanish ibex (Capra pyrenaica) epididymal spermatozoa. To optimize the collection of epididymal spermatozoa, two spermatozoa recovery methods were tested: i) by using small cuts in the cauda epididymides and ii) by the application of air pressure (from a syringe) inside the vas deferens. The percentage of viable spermatozoa recovered was lower (P < 0.05) with the air pressure method. No significant differences were seen in the efficacy of the two diluents as determined by percentage viability of thawed sperm, membrane integrity (as determined by the hypo-osmotic swelling test), or acrosome integrity. The use of the TCG-lactose medium strongly reduced sperm motility (P < 0.001). The sperm samples that had been diluted with TCG-6% egg yolk extender showed a greater incidence (P < 0.05) of morphological abnormalities. TCG-lactose alone, does not well preserve motility when cryopreserving Spanish ibex epididymal spermatozoa.
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PMID:Recovery and cryopreservation of Spanish ibex epididymal spermatozoa. 1835 60


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