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

In vitro fertilization of hamster eggs by ejaculated or epididymal spermatozoa in the presence of seminal plasma or male accessory gland secretions was examined. There was no difference in the penetration rates, the time of sperm penetration and the optimal sperm concentration between ejaculated and epididymal spermatozoa. The swelling of the zona pellucida, a high incidence of polyspermy, distortion of the vitellus and the degeneration of eggs were observed after incubation of ejaculated or epididymal spermatozoa in the presence of seminal plasma or accessory gland secretions. Using ejaculated spermatozoa, the fertilization rates of eggs with or without follicular cells were similar but fertilization by epididymal spermatozoa was inhibited by secretion of the seminal vesicle or ventral prostrate gland but not by that of the coagulating gland or the dorsal prostrate.
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PMID:In vitro fertilization of hamster eggs by ejaculated or epididymal spermatozoa in the presence of male accessory secretions. 90 15

Extracts of about 1600 Indian plants were tested for spermicidal activity. A small quantity of rat vasal or epididymal contents was placed on 2 drops of plant solution, mixed, and examined under a phase contrast microscope. Results were scored positive if 100% of spermatozoa became immotile. Tests were repeated 3 times. and sperm revival tested by addition of buffer to the immobilized sperm sample. Plant extracts showing positive activity were tested on liquified human semen. 30 plants showed spermicidal activity in rats, of which 16 caused instantaneous immobilization of human spermatozoa. Studies are underway on the isolation of active constituents and subsequent structural relationships.
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PMID:Screening of Indian plants for biological activity: Part VII--Spermicidal activity of Indian plants. 91 27

Swelling of the spermatozoan nucleus and decondensation of the chromatim occur soon after penetration of spermatozoa into the egg cytoplasm. This decondensation was duplicated in vitro by incubating pre-ejaculatory ram, rabbit and bovine spermatozoa and also stored post-ejaculatory bovine spermatozoa in 1% sodium dodecyl sulfate and 2.0 mM dithiothreitol. Spermatozoa obtained from the testis and epididymal caput, corpus and cauda showed a progressive resistance to nuclear decondensation, while no change was evident in the decondensation time of spermatozoa obtained from the epididymal cauda, vas deferens and ejaculated semen. There was also a significant increase in decondensation time after the spermatozoa had been stored in vitro at 25 degrees C. This increased resistance to nuclear decondensation in the in vitro stored spermatozoa, reflecting an increase in cross-linking within the spermatozoan histones by formation of disulfide bonds, may account for part of the increased embryonic mortality observed when spermatozoa are stored in vitro prior to insemination.
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PMID:Nuclear decondensation of mammalian spermatozoa: changes during maturation and in vitro storage. 92 69

The ability to form androgen conjugates and the hormone dependency of the conjugating enzymes have been studied in the rat epididymis. Following the in vitro incubation of 3H-testosterone with epididymal slices from intact and castrated rats, the radioactivity recovered was partitioned between water and ether. Examination of the water soluble radioactivity demonstrated the presence of glucuronides and sulfates. The total radioactivity in the conjugate fraction was the same for both intact and castrated animals. However, castrated rats showed a 3-fold increase in the glucuronide fraction with a corresponding decrease in the formation of sulfates. Characterization of the ether soluble radioactivity after solvolysis of the conjugate fraction from castrated animals, showed DHT (17beta-hydroxy-5alpha-androstan-3-one) and 3alpha-diol (5alpha-andro-stane-3alpha, 17beta-diol) to be the main metabolites. After beta-glucuronidase hydrolysis of the same, only 3alpha-diol could be demonstrated at a significant level, although traces of DHT and delta16 compounds were present. Corresponding hydrolysis of the water phase from incubation of epididymis from intact rats, demonstrated a marked quantitative difference. Here approximately 40% of the conjugated aglycones consisted of delta16 compounds, whilst only about 12% was comprised of 3alpha-diol. The preferential conjugation of DHT and 3alpha-diol to a sulfate radical was demonstrated in both intact and castrated rats. Since the conjugated delta16 compounds were detected only in the epididymis from intact animals, it is possible that these are formed by the spermatozoa.
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PMID:Androgen metabolism by rat epididymis. 4. The formation of conjugates. 94 Nov 82

The sera from 48 female rabbits immunized by a series of multiple intradermal injections of washed epididymal, washed ejaculated, and beta-amylase-treated rabbit spermatozoa in complete adjuvant were examined for spermagglutinins by the Kibrick gel agglutination test and a slight modification of the Shulman capillary agglutination test. Control animals receiving the adjuvant or saline usually had no positive titers. All three antigenic preparations produced similar titers, positive at dilutions as high as 8192-fold with Kibrick test and 256-fold with the Shulman test. Maximal titer development was reached 4 to 6 weeks after starting the immunization, and positive sera were obtained from some does for 25 weeks. The correlation coefficients between positive titers obtained by the two tests were r = 0.91 during the first 10 weeks and 0.41 at 15 to 25 weeks after immunization.
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PMID:Spermagglutinin titers and their relationship to fertility in isoimmunized female rabbits. 94 29

Hamster eggs with follicular cells were fertilized by epididymal spermatozoa in two chemically defined media. The proportion of penetrated eggs was significantly higher in a medium for rabbit (16%) than in a medium for rat eggs (6%), but much lower than in Tyrode's solution containing follicular fluid or blood serum as reported by others. The optimal sperm concentration for sperm penetration ranged from 0.5 to 5 X 10(6)/ml but penetration of denuded eggs failed in these media. When exposed to hamster spermatozoa in the rabbit medium containing living or dead spermatozoa of guinea-pig, rat, mouse or hamster, high proportions of denuded eggs (24-96%) and eggs with follicular cells (93%) were penetrated. By exposure of denuded hamster eggs to hamster spermatozoa in supernatant fluid of frozen-thawed guinea-pig spermatozoa, 97% of eggs were penetrated in 8 hr compared to 0% in the control group. Sperm capacitation was also efficiently induced by preincubation of hamster spermatozoa in the supernatant fluid. The fertilizing capacity of hamster spermatozoa was maintained for 12 hr during incubation with frozen-thawed guinea-pig spermatozoa when the concentration of hamster spermatozoa ranged between 10 and 20 X 10(6)/ml. The beneficial factor of guinea-pig spermatozoa appeared to be from spermatozoa themselves, not from the vasal or epididymal fluids. The presence of follicular cells, blood serum, bovine serum albumin, or even polyvinylpyrrolidone in the media is essential for the capacitation and acrosome reaction of hamster spermatozoa. The components of guinea-pig spermatozoa appear to maintain the fertilizing capacity of hamster spermatozoa and stimulate the process of capacitation.
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PMID:In-vitro fertilization of hamster eggs in different media and the stimulating effect of heterologous and homologous spermatozoa. 94 77

The alkaline phosphatase activity was measured in testicular fluid and in epididymal plasma from caput and cauda epididymidis in boars with normal sperm production and in boars in which the number of spermatozoa passing from the testis to the epididymidis was reduced. The testicular fluid and the epididymal plasma from caput epididymidis contained low amounts of alkaline phosphatase in comparison with epididymal plasma from the cauda. This applies to both groups of boars e.g. boars with normal as well as with totally lacking or lowered sperm production. As no fluid resorption takes place between caput and cauda the distal part of the epididymidis must be the main production site for alkaline phosphatase. The production there is not related to the presence of spermatozoa in the duct. In the caput, on the other hand, it seems that the level of alkaline phosphatase in some way is influenced by the sperm supply to the duct.
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PMID:Alkaline phosphatase activity of epididymal contents in boars with normal or reduced spermatogenesis. 95 17

The use of Silastic and of chromic stenting materials for restoration of the patency of the severed canine vas deferens is compared. 12 adult male dogs were bilaterally vasectomized; 5 months later all has vasovasostomies. 6 animals had an intravas chromic stent and 6 had Silastic tubing rejoining the vas. Semen samples were evaluat ed for sperm count, motility, viability, andm orphology as well as for i on concentrations. Sperm reappeared in the ejaculate of all of the dogs in which Silastic had been utilized, but only 33% of the dogs with chromic stents had sperm appearing in the ejaculate. The overall quality of the semen was better in the dogs with Silastic stents; sperm motility, concentration, and viability was significantly higher than in the dogs with chromic stents. Most of the dogs had normal testicular and epididymal histology; 3 of the dogs with chromic stents with unsuccessful anastomosis had abnormal histology with reduced numbers of spermatocytes, spermatids, and spermatozoa.
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PMID:Vasectomy and vasovasostomy. II. A comparison of two methods of vasovasostomy: silastic versus chromic stents. 95 37

The perforatorium of rat spermatozoa was isolated and its protein composition determined. SDS-polyacrylamide gel electrophoresis showed that the organelle is composed of a single polypeptide component with a molecular weight of 13,000. The perforatorium becomes more resistant to solubilization during epididymal transit due to an apparent increase in disulphide bond content. Amino acid analysis of the perforatorium polypeptide revealed a content of 6-5% cysteine.
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PMID:Isolation and characterization of the perforatorium of rat spermatozoa. 95 29

The separation of mouse spermatogenic cell nuclei by sedimentation velocity at unit gravity has been used to determine the timing of histone and "mouse protamine" synthesis, and the turnover of basic nuclear proteins throughout spermatogenesis. Animals were injected with 3H-arginine or 3H-lysine and at various time intervals (2 hours post-label or from 1 to 30 days post-label) germinal cell nuclei preparations were separated on the staput. Labelled histones and mouse protamine were extracted from staput separated nuclei with hydrocholoric acid and fractionated by polyacrylamide gel electrophoresis. Results indicate that histones are synthesized in association with DNA replication in spermatogonia and preleptotene spermatocytes, in pachytene primary spermatocytes and in spermatids stages 11-16, simultaneously with "mouse protamine". Experiments are reported showing that histones synthesized in pachytene primary spermatocytes and in spermatids stages 11-16 are retained in epididymal spermatozoa, while histones synthesized before meiosis are no longer detectable onto chromatin after meiosis.
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PMID:Kinetics of histone and protamine synthesis during meiosis and spermiogenesis in the mouse. 96 73


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